A Diapered Idea

by Tsunogami

Rating: mature
Tags: Slice of Life, Main 6, My Little Pony: Friendship is Magic, Other, Romance, Moondancer, Sex, Science Fiction
Length: 16639

Sometimes even the smartest ponies don't come up with the best ideas themselves.

Wearing a diaper is good, using one is great, but what if a pony could go beyond that? What if a pony could, in fact, be a diaper? Twilight Sparkle never seriously considered the answer to this question until an old friend's obsession proved that with sufficient determination, or sexual frustration, anything is possible.

Contains: the standard from me, diaper wearing, use, and messy diaper sex. Later chapters will contain diaper transformation.

Published 2016-12-24 02:40:01 UTC
Last updated 2018-01-06 00:51:58 UTC

Chapter 1: A Diapered Morning

So far this morning there was no good reason Twilight Sparkle had come up with as to why she should bother to open her eyes. The heavy rain, -yet more unscheduled weather it seemed- pattering against the thick glass of the small square window on her left sounded so much like how it had all thoes years ago when she still lived in the Golden Oaks Library that her drowsy mind could almost imagine she was still there on her narrow but cozy bed, and that Spike would soon be coming up the stairs to ask her what kind of berries she wanted on her pancakes. It was just all too comforting and peaceful for her to want to do anything other than lay there quietly and listen. The damp scent of the rain made the room around her even smell cozier. If she could just keep her eyes shut a little while longer, then that was all the more time she could enjoy the comfort of the past.

Even after all these years, the only thing that kept her tears from trickling out at the thought of what had happened that awful day was knowing that growing in the very center of the wide shallow depression that had once been the charred blast crater marking the place her home of many years had stood, was a lively young oak tree sapling now three ponies high. Applejack, Faust bless her, had grown the thing from an acorn off the original library tree itself. It would still be a few decades until it was as high as the original. Unfortunately, height was only one consideration, for the trunk to be wide enough to build a new library inside…that would take centuries. She could, technically, use a large quantity of magic to force the tree to grow to full size within minutes, but that would result in something a bit artificial looking, it would lack the gnarled structural majesty of a tree grown naturally, and would not be entirely trustworthy from a safety oriented standpoint. Magically derived structures were notoriously unpredictable. And besides, it was unbecoming of an Alicorn to inhabit a ‘new’ home. Canterlot Castle was a millennium old, and the Chrystal Palace, well, that might be a hundred times older still for all ponies these days knew.

‘And as I’m an Alicorn now, I suppose I can wait.’ Twilight thought to herself, eyes still closed. Patience was after all, at least in this instance, a virtue.

A slight movement, a shuffling, and now a gentle nuzzling, brought Twilight out from her considerations on the issue of appropriately grown housing. Incidentally the movement, that of another pony, finally gave her reason to open a single eye. The small bedroom was suffused with a dim light that seemed to trickle in the window much like the raindrops running down the glass. But the light brown wall paneling and timber frame supports lent it a coziness that many a pony would pay some designer handsomely to replicate, probably imperfectly, in their Canterlot townhouse.

Why was it, Twilight wondered idly, that the majority of ponies, her friends included, had manes and tails of a single color or pair of colors, which either nearly matched or in some other way complemented their fur color, but then, once in a great while, a pony would come along with a color pattern that defied convention so blatantly? Both Cadance, Celestia, and herself had three colors in their manes, which was unusual enough, but the pony whose head was pressed up against her right hip –now how had that happened? Had six.

She considered, not for the first time, how many mares, along with most of the stallions, living across the continent of Equestria, lusted after the rainbow maned pony she was laying on the bed with right this moment.

Twilight was not usually a pony to be smug…but that thought, well, that often did it.

Rainbow Dash had a strong, sleek, and youthful body that was always kept in great shape. It had taken Twilight years to figure out that Rainbow didn't just stay healthy for the sake of her goal to become a member of the Wonderbolts, a goal achieved years ago, or as a generally good life style choice, but because there were few things the Pegasus enjoyed more than to be the one who could outlast, outplay, and generally defeat any opponent in any game or event she came across. Her competitive streak was a kilometer wide. This determination to be the victor was rarely more apparent than when it came to sex.

She wasn’t necessarily the dominant partner in her relationships, a fact that had initially surprised Twilight early on in their friendship. She could be unquestionably submissive when she wanted to be, but nothing made her more insufferably pleased with herself than making whichever mare she was with that night cum before she did. Her body, and the shape it was in, allowed her to achieve victory quite often. For a decade Twilight had worked to keep up with Rainbow several times a week. Only after her ascension, a year ago now, had her new and improved physiology allowed her to keep up with, and some nights even win out against, her partner. Perhaps that's why Dash was spending even more time with her recently, she did love a challenge that one.

Twilight considered turning onto her side, she had slept the whole night through on her back, an unusual thing for a pony, and the ache developing between her shoulders was a reminder of that fact. But doing so would disturb Dash, and besides, laying on her side would put pressure on the crotch of her diaper from whichever leg was on top. If it had been dry, that wouldn’t be a problem. However, it was anything but.

The diaper had already been rather wet when she had gone to sleep, completely exhausted by her eventually successful attempt at making Rainbow cum first, an accomplishment swiftly followed by promises of retribution. Now, since having woken up twice during the night to use the bathroom but simply letting it flow into the waiting diaper, it was quite soaked, and her bladder was beginning to ache anew. Her diaper would soon be at its limit and laying on her side was a guaranteed way to make it leak somewhere. What was the point of wearing one of the things if it was just going to do that?

Rarity made wonderful diapers, and they would expand to twice their original thickness when fully wet, but even they couldn’t go on forever. But as long as she didn't do anything too drastic she could stay in this one for a while yet.

‘Might as well get on with it.’ Twilight thought as the rain continued to pour outside.

It was really quite cozy, being in this warm bed in one of the naturally rustic bedrooms on the small second floor of Fluttershy’s cottage. Thank goodness it had a plastic sheet. Fortunately for the pair of them the cottage’s shy owner was typically a well prepared pony. Twilight knew that she would need to eventually get herself up and out for her business in Canterlot today, but first she was just going to remain lying here, wet herself some more, and enjoy how the addition of more pee flowing down and into the back of her diaper would make it even more enjoyable to lie in. Perhaps Rainbow would eventually wake up and relieve Twilight of the possible guilt of disturbing her.

No longer caring what her bladder did now, Twilight simply relaxed herself completely. It was a funny thing, Twilight knew that the spray of urine now flowing freely into her diaper was at precisely her body temperature, yet, it felt so warm, as though it must be a dozen degrees higher still. Perhaps because she knew her pee was warm, her mind made it feel that way more than it otherwise would have. It was something to consider.

Twilight was surprised when a light blue furred leg rose up and pressed its hoof gently down on the front of her diaper just over the gushing warm pee. Twilight smirked to herself, ‘how long had the little devil been awake?’ She wondered.

‘Well, no reason to pretend I am either.’ She realized, spreading her legs just a bit further, letting Rainbow know that she was well aware and approved of where the Pegasus’s hoof was.

The hoof began to rub around in small circles as Twilight continued to wet. In response she began to lift her butt up to press herself into the roaming hoof. Twilight knew that this escalation in her response would only ever end one way and that doing so would bring to a certain end any sense of a calm, drowsy start to her morning.

She didn’t give a damn.

Twilight’s diaper did an admirable job of absorbing yet another full bladder’s worth of stored urine into its thick padding, the dark stain nearly spreading into every corner of the diaper. However, it had long ago given up on being able to absorb the moisture enough to pull it away from her sensitive skin and lavender fur, giving her most enjoyable parts an all-but-literal bath underneath all the hot wet padding.

Twilight was disappointed when having finally finished her morning wetting, and the pee trickling to a stop, that so too did the hoof rub. Twilight opened her eyes more fully this time, and using her foreleg’s knees, raised her upper body off the pillows and bed so she could look down to see what might be done to get the hoof to resume its work.

Twilight’s diaper, one of a type designed by Rarity, had a good quality smooth plastic surface, one that wouldn’t tear when the tapes were pulled, that was a medium lavender around the waist and leg holes and a very light lavender everywhere else. Small purple five-pointed stars decorated the sides of the diaper and the tapes themselves were a light soft green color that Twilight wouldn’t normally have thought would go well with her coat but seemed to complement it anyway. The diaper certainly had swelled up nicely, the light lavender coloration of the plastic now seemed a bit off due to the mild yellow of the liquid it contained. The subtle yet obvious smell of a hot pee once again began to mix with the pleasant early-morning rain scent that had been so relaxing before. This new smell was another nail in the coffin of her morning drowsiness.

Right next to her thick and warm diaper was the upside-down face of a smiling pegasus who knew exactly what it was she had started.

Rainbow Dash quickly turned over and stood up from where she had been laying with her cheek against Twilights diapered hip upon seeing that the alicorn was now very much awake.

Rainbow stretched luxuriantly, showing off her own diaper. The diaper itself was a bit more streamlined than what Twilight had on, the plastic surface was thicker than a standard diaper, a functional choice Rarity had insisted on when designing it so that it would keep its shape better and stay smooth and sleek no matter how much walking, running, flying, or…other activities the pegasus got up to while wearing it. The waist of the diaper came up a little further on Rainbow than it did on Twilight, helping to keep the diaper’s image as one appropriate for an active pony due to making the diaper look even more streamlined. Most of the diaper was a light grey blue but with three wide parallel navy blue strips running from the top of the front all the way around to the tail hole in back. On top of the blue strips, front and center on the diaper was a large print of Dash’s cutie mark.

As much as Twilight loved seeing Rainbow in her diapers and how good she made them look, it took some effort to not immediately roll her eyes at the blatant example of vanity. Even if it was very cute vanity.

Looking up at the underside of Rainbow Dash from her position she could easily tell the diaper was soaked to bursting despite the diaper’s color not being one that indicated wetness as well as plain white plastic would have. That diaper had been completely dry when Rainbow had gone to sleep so far as Twilight could remember. Perhaps there actually was something to that vulgar joke about having to pee like a race h**se.

“So….ya’ like what you see?” Rainbow Dash asked, classic smirk fixed firmly in place.

“You know you don't need to ask that, not after what we did last night anyway.” Twilight responded, again trying not to roll her eyes.

“Hmm… about that, I seem to recall you…winning… that round.” Rainbow said the word as though it she was being forced to eat hoof tacks.

“I think it’s time for a little payback, and I’m not goanna let you leave here without settling the score, and from the way that diapers’ looking I won’t have to try too hard.” The six-colored pony said.

Twilight had to admit to herself that Dash was probably correct, bathing her pussy in hot pee while watching Rainbow in her own diaper had excited her to quite a degree. And frankly her desire to ‘win’ at, well, anything really, appeared to have departed her sometime during the night. Simply laying back and letting the pegasus get to work seemed quite alright with her.

“Ok Dashi, do whatever you want. I can tell when I’m not going to win.” Twilight said as she let herself fall back onto the smooth clear plastic of the bed sheet and spread her legs a bit wider in invitation.

Rainbow actually managed to look almost disappointed at the lack of any resistance from Twilight. Probably because getting Twilight to cum first didn't mean as much when the mare wasn’t going to do anything to try and resist her orgasm.

‘A hollow victory’ Twilight thought to herself with a private smirk that she made absolutely sure Rainbow didn't catch. This annoyance will only make Rainbow try harder to correct for next time they really went at it. It was rather devious, using Rainbow Dash’s psychology against her to ensure even better sex in the future this way, but then, any princess, even Celestia- actually, especially Celestia, needed to be able to be subtly devious from time to time.

A cool breeze began to blow between Twilight’s legs as the tapes were pulled back on her diaper. Rainbow did this job one tape at a time using her teeth. Not so much because she had to, but because it drew out the process, increasing the anticipation. Rainbow then pulled the front of the soaked diaper off Twilight and let it flop gently down between her spread legs, exposing a lot of pee soaked fur and a glistening slit at the center of it all.

“Huh.” Rainbow muttered.

“I’m surprised you haven’t messed at all since last night, you know, since you like to so much and all.”

Twilight tried her best to shrug while lying on her back.

“Haven’t had too I guess, and anyway, you know I don’t like to mess right before going to bed.” Twilight replied

Rainbow snorted.

“Yah, because it makes you too horny to sleep, all that poop in your diaper, you know, smearing itself all over your slick pussy…”

“Yes, yes, alright! Just get on with it Rainbow!” Twilight said in exasperation.

Some mares like Rarity would have then taken the opportunity to further tease Twilight by slowly drawing out her pleasure with a thousand little practiced tequnique designed specifically to make a mare ‘almost’ cum for hours.

Rainbow Dash, on the other hoof, having realized that verbal teasing time was at an end, dove muzzle first into Twilight’s pussy like a starving pony into a bowl of blueberries.

Dash was perfectly happy with eating out any good looking mare under normal circumstances but the smell and taste of piss along with the fresh plastic scent of the disposable diaper that held so much of the yellow liquid, was more than she could resist.

Twilight’s smooth cum-slicked lips were an utter delight beneath the pressure of her tongue, and knowing that they had spent the night being held protected and warm under all the soaked padding of Twilight’s diaper made this probably the best clit in all of Equestria Rainbow could have her tongue inside of right this moment. She made sure that not a single millimeter of the delicate flower under her muzzle escaped her attention and was rewarded with Twilight arching her back and groaning loudly at nearly everything she did.

Twilight for her part, once again found herself completely at the mercy of Rainbow’s abilities and with no desire to do anything about it aside form letting it go on as long as possible. She was still dimly aware of feeling the wet diaper under her butt adding its own pleasure to the experience.

When Rainbow opened her jaws wide enough to hold on to her whole pussy at once between her lips and jam her tongue into her clit, Twilight came into Dashi’s mouth as though she had released a quick hard burst of pee. She could actually hear it splatter across Rainbow’s teeth.

Suddenly feeling drained of strength, Twilight flopped back onto the bed with a loud sigh as Rainbow licked her lips and leaned in for a kiss. Twilight happily accepted and as their tongues intertwined Twilight was able to enjoy the taste of herself mixed with a faint bit of urine, which she enjoyed in small quantities such as this.

After a few seconds, which somehow seemed rather longer than that, they broke away and Twilight again levered herself up to a sitting position and from there onto all fours by half turning, half sliding out of the bed.

“Huh? You’re not going to put your diaper back on?” Rainbow asked looking mildly surprised. Probably taping Twilight back up into her already thoroughly soaked diaper had been the next thing on Rainbow’s list of fun and sexy things to do with her this morning.

“I’m sorry Rainbow.” Twilight said catching the sound of disappointment in her voice.

“I need to take a shower and get myself to Canterlot soon. I might take the diaper with me to put on later, but it won’t do to be seen wearing the thing all about in public.

“Well, I don’t mind seeing you wear one in public.” Rainbow said in her version of a reasonable attempt at earnest seriousness.

“I know you don’t, Dash.” Twilight said smiling.
“But there are some… interests that ponies enjoy that really don't fit well with their public lives. As you well know.” Twilight replied, almost taunting.

“The other ‘bolts know I wear diapers under my flight suit, Spitfire certainly does…” Rainbow couldn’t help adding.

“Maybe they do, but they are your friends and you all know quite a lot about each other’s private lives. How well would it go over if you performed at some large public event in just a diaper and no flight suit?” Twilight asked.

Rainbow quickly glanced down at her diaper and cringed at the thought.

“Ok, ok, point taken. A princess can’t show off thoes strong leadership qualities if she goes about everywhere in a diaper.” Rainbow said with a slight huff.

“Exactly. There is a time and place for engaging in one’s sexual fetishes and a time and place for good governance. Unfortunately, the two don’t often overlap.” Twilight said, knowing as she spoke that she was falling into the role of guest lecturer at the university.

Rainbow simply looked at her with a bemused expression while sitting on the edge of the bed in a way reminiscent of a certain mint green and white pony who could always be found in the same position on Ponyville park benches with her marefriend.

“Right, yes, well, time for my shower.” Twilight decided out loud, unsure of the best way to smoothly disentangle herself from this conversation.

As she trotted across the room the faint sounds of a giggling Rainbow dash followed her as she went towards the bathroom door. Not that Rainbow would ever admit to having ‘giggled’ about anything.

****

As a gentle spray of warm water from the little shower in the single upstairs bathroom washed the last of the night’s pee from her fur and the lightly basil scented shampoo made said fur shine again with a luster which had been lacking of late, Twilight considered Rainbow’s diaper and the way it looked on her athletic body. How its thick plastic surface always glistened with reflected light, looking almost wet, even when the diaper itself was dry. A bit ironic that. Also, how Rarity’s design managed to give the diaper a strong sense of thickness and bulk between the legs and over the butt without actually looking so bulky in the way a baby diaper often did. Twilight figured, not for the first time, that it had to do with Rarity’s expert knowledge of proportions. It was almost like the diaper was emulating the form of its wearer. Which, Twilight knew, was exactly the effect Rarity had in mind when she had made it, and all the others like it, for Rainbow. Some other athletic ponies, or so Rainbow had told her, made due with pullups. Not that pullups themselves were bad per-se, but Rainbow had insisted, and Rarity agreed, that the pegasus deserved true diapers, and the best possible at that. The pony tended to pee quite a lot and had never shied away from pushing a large squishy mess into her diaper whenever the need arose. Pullups simply were not designed to deal with all day, and sometimes all day and night use without a change. Also, no matter how much Rainbow managed to wet them they never seemed to swell up quite as much as Twilight’s diapers did. As though the absorbent material in them was slightly different. She really ought to ask Rarity about that at some point.

Twilight became aware that she was beginning to feel quite excited again just by thinking about diapers so much. Which was funny because a pony would think that having just been licked to orgasm by a mare like Rainbow Dash might have more to do with her present arousal. Well, in a way it had, Twilight supposed, but diapers were what made the whole situation too sexy to ignore.

Just as she turned the little metal handle with a hoof tip to turn off the water while concurrently fetching her towel with her horn to work on getting dry as quickly as possible, she had been thinking idly in the shower longer than was necessary after all, she became aware of a growing need to use the bathroom. The pressure sort of snuck up on her like Pinkie Pie was known to do when in one of her prankster moods. One moment she didn't feel anything, and by the next she knew that whatever she did it would involve having to poop in just a few minutes. There was no way to keep a feeling this strong contained for long.

“For the love of Cadance!” Twilight growled to herself with teeth clenched.

‘I’ve just spent the last twelve, no, fourteen hours wearing a diaper, and as soon as I take it off I have to go like this?’ Twilight thought to herself in annoyance.

“Ugh! How typical.”

“Although…”

Twilight suddenly realized that unless Dash was planning on going somewhere today that there was no reason she could see that the rainbow pony would have reason to take off her diaper while she had been cleaning herself up in the shower.

This meant that in a way there was still a diaper she could use where all this nice poop her body had been storing up wouldn’t go to waste.

Twilight emerged from the shower accompanied by a cloud of the warm steam that had built up to near sauna like levels in the small poorly ventilated bathroom. As soon as it made contact with the glass in the small windows of the bedroom beyond they immediately fogged up, obscuring the outside view completely.

To Twilight’s puzzlement Rainbow was sitting upright on her bed, her back to the wall and with her diaper untapped so the front was laying open between her legs. The once bright white padding was a light yellow color, and had been so since the previous evening. The new addition was a brown smear coating the inside of the diaper immediately under the cyan pony’s butt. Dash had a hoof pressed against herself near the top of her narrow pink slit. Its bottom half was coated in the same stuff that was under herself.

However, instead of being in the midst of pleasuring herself like Twilight had immediately thought, Rainbow seemed to simply be contemplating the situation between her legs with slight disappointment.

Seeing Twilight standing there with a questioning look on her face, Rainbow ‘s expression changed from disappointment to slight annoyance.

“I thought I felt like I had to go enough that I would make a poop that would be worth enjoying in diapers like this, but I didn't wind up going as much as I thought I would…”

Twilight could only smile broadly, thinking how this was turning out to be an even better situation than she had planned for.

“…What?” Rainbow asked with a suspicious look on her face, seeing how Twilight’s reaction was not the one she had been expecting at all.

Twilight didn’t say anything at first, simply removed the large fluffy green towels wrapped about her midsection and tail and stepped up onto the bed. With a burst of telekinetic power, she lifted Rainbow Dash, open diaper and all, away from the wall she had been leaning against, and laid her back down so that her head was resting on the pillow Twilight had been using when she had woken up.

“What are you up to Twilight? Rainbow asked, surprised at her sudden relocation. It was generally considered rude for a unicorn to touch another pony magically, to say nothing of lifting them up into the air, without at least asking permission first. Even when having sex, that was not something Twilight did much of. So doing it now, implied a certain level of impatience or arousal on Twilight’s part. Briefly Rainbow had time to consider that perhaps it was both.

“I’m simply assisting you with your current problem.” Twilight said.

“Now, scoot back a bit.”

Rainbow did so, shuffling her butt several centimeters back from where it had been resting on the diaper and revealing a modest mess. Certainly more than a skidmark, but rather less than enough to result in a properly filled diaper. Twilight understood her friend’s annoyance, it was the perfect amount of poop to feel just good enough in a diaper to leave a pony desperately wanting more.

Twilight was proud of herself for not rushing the procedure too much up till now, but she was a hair away from losing containment – so to speak, and doing so anywhere but her planned location would be a criminal waste. It was all she could do to keep her anus closed while getting Rainbow to adjust herself into the proper position.

As soon as Twilight was satisfied, she immediately stepped over to put two legs on either side of her on-again, off-again marefriend, positioned her butt just over a spot on the diaper that she calculated would be halfway between where the diaper would cover Dash’s anus and clit and relaxed all the muscles in her butt.

A huge load of soft squishy poop burst out of her rectum and flowed, glistening in the dim morning light, right down onto the exact spot Twilight had chosen. The consistency of the poop began to change from creamy at first to more liquid and runny towards the end, almost splattering out of her. The result was a large pile of soft light brown poop, slowly spreading outwards. Twilight couldn’t resist a sigh of relief as the pressure in her butt suddenly disappeared.

“There! What do you think of that?” Twilight asked Rainbow, who was trying to get a good look at the pile that was now pressing up against her butt as she lay there. The position was a bit of an awkward one for any pony because it required her to have her tail bent backwards underneath herself. Pony tails were very flexible, but they could only take so much for so long.

"Sweet Celestia Twilight! this is so nasty...and hot... mmmm..." Rainbow moaned as she slid her butt forwards in the diaper just a bit, pressing her pussy into the mound of squishy poop that was slowly spreading outwards.

"I think I should tape up this diaper before you just cum right as you are." Twilight suggested.

"Would that really be so bad?" Asked Rainbow.

"What are your plans with Fluttershy?" Asked Twilight with an eyebrow raised.

“Ah, right, well, uh, I guess you did solve my problem at any rate... Rainbow Dash said, a grin growing on her face.

Twilight simply smiled.

"Yah, well, help me get this thing taped on so I can get up then.”

“Ok, but the only way to make sure this works without anything squishing out the leg holes is to properly allocate the poop to as much of the inside of the diaper as you can.” Twilight responded.

Rainbow Dash smirked.

“You mean smear it around a bunch.” Rainbow said dryly.

“Yah… Twi, this isn’t my first messy diaper, ya know.”

“Ok, ok.” Twilight said, a little abashed. Though she felt that the pegasus could show a bit more appreciation to the young alicorn who had just filled her friend’s diaper with enough poop to be worth at least two good regular messings.
“But you do realize that this diaper isn’t so much ‘your’ messy diaper anymore is it?” Twilight couldn't help responding.

“Ha, ha. Ok, you’re right, thanks Twilight. Now, can you tape this up please, it…I want to feel it better.”

Smiling down at her friend Twilight again lifted Rainbow’s butt up a few centimeters above the diaper, and using her magic, -she was tempted to use her hoof directly for this task, but she had just gotten out of the shower after all- she began to smear the huge pile of warm gooey shit all over the inside of the diaper from the top of the front to half way up the back. It was oddly similar to the way she had seen Pinkie Pie use a knife to spread icing on a cake.

Having quickly completed this task she levitated the open shit smeared diaper, and in one swift motion folded it around and over the waiting pony’s butt and crotch, taping the four tapes tightly over the front and instantly coating everything inside the diaper in her gooey, runny poop.

Rainbow Dash let out a quite un-characteristic whimper of pleasure as she was lowered back down onto the bed and its protective clear plastic sheet. Her fore hooves immediately pressed themselves into the front of the diaper and her whimper became a groan. With Twilight’s mess so evenly spread out, no one place had enough of the stuff to easily squish out the leg holes or the top or back of the diaper no matter how Rainbow sat or laid or squished around. Even a good diaper humping wouldn’t produce much in the way of escaped mess. However, there was sufficient quantity that the areas around the leg holes would quickly, if they were not already, beginning to show an obvious spreading brown stain. An effect Twilight found rather sexy. At first glance all this effort of spreading her mess around evenly might seem like a peculiar manifestation of OCD, but in fact it had a quite practical purpose.

“So, it seems I’ve done my job to make up for your own body’s lack of results for this morning. I hope you enjoy my mess as much as you know how. It and your diaper deserve that much I think.” Twilight said, an edge of playfulness entering her voice.

“I guess this means I owe you one, doesn’t it.” Rainbow said, not really saying it as a question.

“Damn straight, you sexy mare.” Twilight said in a way that Cadance would be surprised by, but very proud of.

Dash’s eyes widened a bit but she broke out into laughter.

“I guess I’ll be seeing you again soon then won’t I.” She said, still smiling broadly up at the lavender alicorn.

“You bet!” Twilight said, smiling back.

****

Having packed her saddle bags to her satisfaction, a process that included the addition of the soaked diaper she has spent the night wearing, Twilight walked from the living room to the kitchen through a narrow door to find that the cottage’s owner had finally emerged, a bit drowsily, from her own downstairs bedroom, and that Rainbow Dash had apparently found her first.

Fluttershy was standing at the kitchen counter, in the process of fixing herself a small bowl of cereal. Her light pink mane and tail were a tad frizzy with strands sticking out a bit haphazardly here and there. Obviously the pony had only just gotten herself up out of bed. Twilight wondered if that had been all Fluttershy’s idea or if Rainbow Dash had come barging in on the poor pony and forced the issue. If the latter, she would have to give Dash a good lecturing about it. Fluttershy’s bed mane only served to add to her innocent appeal to Twilight’s eyes. Always the vulnerable seeming one, Fluttershy was. Though that appearance could be, Twilight had found on occasion, an uncommonly deceptive one.

Twilight’s eyes were quickly drawn to the sleepy mare’s appropriately adorable disposable diaper. It was extra thick, more so than either Rainbow’s or even Twilight’s. The diaper, bulky even when dry, positively bulged in all sorts of wonderful ways as it was absolutely drenched with pee. Very little of the originally bright white plastic surface of the diaper remained pristine. A double row of pink butterflies was printed on the slick surface, running from the top in front, around the tail hole, to the top in back. Now, an off white, slightly yellow color completely dominated. The diaper was very well made and taped on tightly, so despite being so heavy with pee, it hardly sagged at all. Twilight could imagine how so much warm urine being held so close against Fluttershy’s body must feel. The pony must have been wetting the diaper for over a full day to achieve this effect, it was not often Twilight had approached such an extreme state of total saturation.

That was probably why Fluttershy kept the thing on so long, Twilight thought, it must be a very comfortable and pleasurable sensation to be walking around or sleeping in such a thick, bulky mass of warm soaking wet plastic. Coming nearer, Twilight could see little droplets of pee trickling down Fluttershy’s back legs, leaving a trail of little spots on the hardwood floor wherever she walked. The pony seemed utterly unconcerned by the slight leaking, paying no attention to it. Twilight herself didn't enjoy a leaky diaper as it usually meant the diaper itself was of lower quality, and even if that was not the case, it still produced a mess to clean up wherever she had been. But on Fluttershy, the urine trickling down the mare’s hind legs was somehow…enticing.

Though, Twilight noted that an additional reason the diaper may be beginning to leak had more than just a little to do with how much pee it contained, seeing as how Rainbow Dash, who was standing behind and just to the side of Fluttershy was pressing a hoof into the bulky soaked padding below Fluttershy’s tail.

Grinning at Twilight as she entered the room, Rainbow Dash seemed to find the lavender alicorn a suitable audience to perform for, and escalated her activities by abandoning the hoof rub and mounting Fluttershy, diaper and all, like a stallion preparing to give the yellow mare a good rutting.

Twilight watched from the entry to the kitchen with a growing feeling of arousal as Rainbow Dash curled her forelegs about the base of Fluttershy’s wings, which were beginning to stretch out from her own increasing excitement, in the way of any aroused pegasus. Fluttershy lifted her tail up and to the side removing the last obstacle that would prevent their diapers from coming into full contact.

With a soft squeak of plastic on plastic the two ponies’ diapers pressed into one another, more drops of pee emerged from around the leg holes of Fluttershy’s diaper and the strong smell of Twilight’s own poop emerged even more powerfully from Rainbow Dash’s diaper. Twilight could see the cyan pony’s diaper was beginning to show signs of its mess-slicked insides as its color was changing from the light grey-yellow of a wet diaper to the grey brown of a very messy one. And the way that the wrinkles in the thick plastic surface of both ponies’ diapers around the tightly pulled tapes were shifting around as Rainbow Dash rhythmically humped Fluttershy’s diapered butt was really rather hypnotic.

Fluttershy’s wings were hard and stiff now, sticking nearly straight out to either side of her, an effect now being mirrored by Dash’s own wings. Fluttershy, cereal bowl quite forgotten, was keeping her front legs up on the counter top and sticking her backside out as much as she could, bending in a delightfully arched way to give Rainbow Dash the best round diaper butt possible to grind against. Apparently now quite uncaring as to whatever manner had been used to awaken her in the first place.

Twilight’s own pussy grew wet as she considered how her own slick poop was being smeared into every glistening fold and crevice of Rainbow’s pussy lips as the athletic pegasus slowly but firmly pressed her diapered crotch into Fluttershy’s padded butt. The continued slick rubbing sound of plastic on plastic of the diapers was wonderful all on its own.

The two pegasi seemed utterly lost in their own mutual world of diapered pleasure, Rainbow in her sleek and slick yet still thickly padded diaper full of borrowed poop, and Fluttershy in her more round and puffy diaper, absolutely bulging with multiple wettings.

‘What a perfect pair of friends.’ Twilight thought staring at the two of them.

Resisting the urge to retrieve her own wet diaper, now neatly folded up in her saddle bags back in the living room, Twilight fought down her desire to join in the fun and got herself her own bowl of cereal from the cabinet next to the sink. Though by no means did she ignore the performance of the two mares as they continued to find new and entertaining variations on the theme of pressing crotch against butt.

As Twilight progressed through her cereal, Rainbow became more and more insistent in her motions and as the last of the contents of Twilight’s bowl were eaten, Rainbow Dash came in her diapers with a judder and a groan, sliding her crotch up and down in long smooth movements over the roundness of the diapered butt she was bent over.
Twilight couldn’t help the heat in her cheeks, a companion to the heat still located between her back legs, as the two diapered mares joined her at the small round wooden table.

“Bet you liked that, didn't you Twi!” Rainbow said looking quite pleased with herself.

“I couldn’t help but notice who came first that time, in fact I don't think Fluttershy came at all.”

“Did you?” Twilight asked turning her attention to the yellow pony who had just sat on her chair slowly, savoring how the pee saturated padding of her diaper pressed itself against her.

“Um, no… not yet.” Fluttershy said looking down at the table top and not meeting Twilight’s gaze. Though the mare was smiling a bit as she spoke.

Rainbow managed to look almost offended.

“Fluttershy isn’t a pony I can really, I don't know, rush? I guess.” Rainbow said, trying to figure out how best to phrase her thoughts.

“I’ll make her cum today, I don’t give up that easily, but she will only cum when she’s been really horny for a long time, you know.”

“So in other words, you can never win with Fluttershy, she’ll always outlast you, so you don't even try.” Twilight said, smirking around a mouth full of cereal.

Rainbow scowled back at her.

“Now hold on, that's not what I meant, I- “

Dash cut off her rebuttal upon realizing Fluttershy was quietly giggling to herself, still not looking up at either of them.

As she and Twilight both turned to regard the shy pegasus, Fluttershy got up off her chair and walked over to Rainbow who was regarding her with curiosity.

“I just know you will try your best Dashi.” Fluttershy said quietly and gave the surprised pony a quick kiss on her cheek.

As she walked away from the table and towards the living room where Twilight had been before coming to look for some breakfast, Fluttershy paused in the doorway between the two rooms and spread her back legs slightly. Twilight watched as the pink maned mare grunted softly and the back of her thick, soaked diaper expanded outwards right under her raised tail with a faint sound unique to only one bodily function. Twilight realized that for Fluttershy’s extra thick diaper to have expanded so obviously in back, the mess the pony made must have been quite considerable in quantity.

“You know where to find me, Dashi” Fluttershy said turning her head to look back at Rainbow with a shy but surprisingly sultry smile.

With that she walked off into the living room and around the corner out of sight. A few seconds later the two ponies still in the kitchen heard her bedroom door open, then close with a soft click.

Rainbow looked at Twilight, grinning ear to ear.

“I think there’s something I need to do.” Rainbow said standing up quickly.

Briefly Twilight wondered if Rainbow’s pun had actually been intentional.

“Enjoy yourself Dashi, I’ll be back to see both of you late tonight. It looks like you will have plenty to keep you busy while I’m away!”

Rainbow Dash was already halfway to Fluttershy’s bedroom before Twilight finished speaking.

Chapter 1.5: A Diapered Diversion

The problem with being turned on, Twilight decided, was that it rather acted like a fire in the mind. Even if it had mostly been put out, all that was needed to re-ignite a blaze was one single hot spot. And it was this issue that Twilight found herself facing barely a minute after departing from Fluttershy’s cottage. The idea that Rainbow and Fluttershy were having hot diapered sex this very moment while she was off to work in Canterlot was not only frustrating because she knew that if she had stayed she would never work up the desire to fly the distance to the castle for only a half day of planning and meetings, but it was doubly so since no matter how she thought of either Rainbow or Fluttershy, even when considering such pedestrian matters such as what Flutters would consider to be the best squirrel food, she was reminded that diapered sex was a thing. It was this concept that she found keeping the spark of arousal hot in her mind.

As Twilight flew over Ponyville she came to a decision, either take drastic action now, or spend the rest of the day only being able to partially concentrate on what was going on around her due to a certain desire.

As she had by now passed beyond the edge of town she banked hard around and descended. Aiming herself towards a fancy looking two-story circular structure perched on the edge of Ponyville. If Rarity was in, and Twilight suspected she was as the pony had just spent several days in the capitol and was probably resting a bit, then there might be some relief for her yet.

Landing with a soft ‘thump’ Twilight touched down in the knee- high grass besides a stone path located behind the Carousel Boutique and walked up to the back entrance, a door through which only delivery ponies and certain kinds of customers would head towards.

Ascending the steps brought her near enough for a few gentle taps on the door with the tip of a hoof.

Twilight’s sensitive hearing allowed her to catch a few mumbled comments about inconsiderate ponies and what time it was, which reminded Twilight, perhaps a bit late for preventing embarrassment, that it was indeed still rather early in the morning.

A small slat slid open in the door and a single eye peered out at Twilight.

“It’s simp- Oh… Um, good morning Twilight, um… I do… well I do suppose you may come in…”

Rarity unlatched the door and opened it just wide enough to allow Twilight to slip inside and into the back workshop. Whereupon Rarity swiftly closed and re-latched the door.

As soon as Twilight turned around she immediately identified the reasons that her friend had for her hesitation in allowing Twilight inside.

First of all, Rarity had apparently done nothing to keep her mane or tail in their usual perfect arrangement so that hair was sticking out at interesting angles and much of her coat looked like it had been petted backwards by a giant hand. The second reason, and assuredly the more obvious to anypony who did not know Rarity very well was the presence of a very thick disposable diaper hugging the mare’s butt and thighs. It was mostly white but was printed in several strategic locations with silver versions of the wearer’s cutie mark and instead of white was light pink around the leg openings and around the top of the diaper’s waist. However, the majority of the white plastic of the diaper was subtly tinted a light tan color. A shade Twilight recognized as the result of a lot of pee mixing with a big load of poop that had soaked completely though the padding.

The smell permeating the workshop confirmed what Twilight’s eyes were telling her.

Twilight had to pause for a moment to consider that as this was Rarity, if in fact she was more reluctant to let anypony see her in this state more because of her messed up hair and fur than because of the diaper.

She decided that it might be a draw.

“I’m so sorry Rarity, I didn't consider how early it still is, and you just got back last night didn't you?” Twilight said before Rarity could say anything.

“Oh, um, yes…I did, but not to worry. I was already up and about, have been for a while, actually. It’s just that I wasn’t expecting any company… as you can see I suppose. So, what brings you by then?”

“Oh that.” Twilight started, now feeling a bit ashamed of herself, appearing unannounced at her friend’s back porch only an hour after sunrise looking for quick sex. It really was rather shallow of her now that she thought about it.

But on the other hoof, she couldn’t just simply leave now that she had intruded this far.

Though still feeling bad about it, Twilight couldn’t help explain herself truthfully.

It’s just that, well, I’ve got to go to Canterlot today and I happen to know that Rainbow and Fluttershy are getting to spend a lot of um, quality time together today, and I was in too much of hurry to properly take care of my needs before I left from Fluttershy’s cottage and I can’t go back there now because if I do I’ll get involved in what they are doing too much and by the time we get that all over with half my day will be gone and I can’t have that happening so I need to do something about my situation and quickly and…”

Twilight trailed off, realizing she was rambling on at an ever-increasing rate of speed. And because she realized that the whole time she had been speaking she had been gazing fixedly at the big, thick, and very comfortable looking diaper Rarity had taped about herself.

It was only after tearing her gaze from the diaper and back towards Rarity’s face that she saw her friend was smiling quite broadly. This was a much better result than the scowl she had been half expecting.

“So Twilight dear, let me get this straight, you got yourself more horny than you realized this morning thanks to our two dear friends and now you need a quickie because if you don't do something you’ll be desperate for sex all day? And you came looking for me to help?”

“Hehe… yah…that, that's about it, yah. Twilight said awkwardly, absently rubbing one foreleg with the other.

“Well, I suppose you've come to the right place then haven’t you.” Rarity said, still refusing to look annoyed.

It took a second for Rarity’s reply to sink in, but when it did Twilight couldn’t help blushing deeply. She found herself thankful that most of her face was covered by fur to hide the color change.

So, if that's what you’re hear for, get thoes saddle bags off and raise your tail.

“I…yes, ok.” Twilight said.

Caught off guard but the abruptness of Rarity’s request Twilight wondered if perhaps the pony did in fact just want to get back to sleep.

But then the grin that Rarity was doing a poor job of concealing suggested otherwise.

Twilight did as instructed and laid the saddlebags down by the wall and turned her butt towards the other mare and waited. Though she couldn’t help keeping an eye on Rarity to see what she did.

Rarity held her diaper up with her horn as she began to untape it, obviously not wanting to let it just plop down onto the floor. Having undone only two of the four tapes rarity turned a sidewise glance at Twilight.

“You do realize my diaper is rather soiled in front right? So it's a bit you know…”

Twilight knew exactly what ‘it’ Rarity was referring to.

“That’s exactly what I was hoping for you know.” Twilight said now smiling herself.

“I thought so.” Replied Rarity.

Having made sure the both of them were on the same page, Rarity continued with the removal of her diaper. Twilight shuddered a bit in anticipation as Rarity lowered her bulky diaper to the floor and neatly folded it over on itself and laid it on a chair.

Rarity’s thick black shaft was now fully exposed and rock hard. The same light brown goo that filled the rest of the diaper was smeared along its length, occasionally dripping from her large heavy balls.

The smell that came from between Rarity’s legs made Twilight want to gag, but was oddly intoxicating all at the same time as though one part of her mind associated the stench with great pleasure but the other part was disturbed by this very association. Fortunately for the sake of sexual gratification, the association with pleasure won out and she lifted her tail and felt her wings spread out in growing anticipation.

“I’d just like to know Rarity, before we begin, how long you’ve been like that in your diaper?”

“Oh, well let’s see now, I went quite a lot almost as soon as I got back last night. I of course made sure to squish it up into the front of the diaper, you know.”

“Of course.” Replied Twilight, grinning.

“Anyway, I went to sleep soon after, too tired for anything else you see. Then this morning, less than an hour ago I messed and wet again.

“Your penis has had a nice long time squishing around in your poop then hasn’t it.” Twilight observed dryly.

“Its enjoyed a very long and pleasant poop bath, yes. Which is why I’m now quite pleased you so conveniently dropped by. I was getting increasingly horny in my diaper, and something was going to have to be done eventually.”

‘Was that a pun?’ Twilight wondered silently.

“Then what would you have done if I hadn’t come along?”

‘Well if it wasn’t then it is now.’ Twilight decided.

“Oh, Sweetie Belle’s asleep upstairs. I suppose I would have gotten around to asking her for a favor or two eventually… but this way she can sleep in a while longer.”

“I see.” Replied Twilight.

The fact that Rarity’s only truly constant girlfriend was her own younger sister always managed to make Twilight feel a little less unusual in her own sexual preferences. Which was a feeling that she wasn’t sure she should communicate to Rarity. Though in the unicorn’s defense, if Shining had been a mare… Well, Twilight had Cadance which made for a good enough consolation prize.

“So, you ready Twilight”

“Absolutely! Oh, and Rarity?”

“Yes Twilight?”

“Please don't be gentle.”

“Yes Princess.” Rarity replied as she pressed the poop smeared head of her thick black shaft against Twilight’s wet pussy.

With a satisfied grunt Rarity mounted Twilight and plunged her messy shaft deep into Twilight’s tight vagina all in one smooth swift motion.

The sensation of suddenly being so full between her legs and of the slick poop providing additional warm lubrication proved enough to cause her front legs to fail in supporting her body. As her front slumped to the floor her backside stayed high in the air providing Rarity plenty of opportunity to thrust herself as deep inside Twilight as she could get.

She clenched herself around the long thick penis filling her and felt too the sticky, squishy feeling each time Rarity’s poop covered balls were pressed up just under Twilight’s dripping clit.

With what was left of her ability to think Twilight decided that having hot messy poopy sex with a mare as capable as Rarity on a morning like this was one of the best ideas she had had in ages.

Rarity thrust and thrust again, each time letting out a new type of moan or grunt along with plenty of squishes and squelches as the two pony’s organs pleasured each other.

“Hey Twilight…I wonder, by the time I’m done, will I have filled you with more of my cum…or my shit?”

“I don’t really care, Rarity, as long as it’s a lot of both!”

“Ohhh, just what I wanted to hear…”

Conversation ended as Rarity’s thrusting became more insistent and less regular as she pressed in harder and held herself inside for longer.

Twilight knew Rarity was about to cum when she leaned over Twilight and held her body tightly between her forelegs.

As thick cum gushed deep inside of Twilight, Rarity made more a series of loud panting gasps than a real scream and she shuddered and trembled as the warm thick ejaculations mixed with the nearly liquid poop that had been accumulating inside Twilight with each intrusion of Rarity’s member. Such was the composition of the slimy fluid that now bathed Rarity as she held herself inside her alicorn partner.

Twilight for her part was unpleasantly surprised, she was close, yes, but Rarity had come too quickly, a very armature move from a mare so supposedly experienced.

“Uh, Rarity, I haven’t-“

“I’m not done yet Twilight, just hold on.” Rarity interjected.

Almost as soon as Twilight wondered what Rarity’s plan was, she felt it.

A hot powerful flow of pee erupted out of Rarity’s still very hard penis and exploded deep inside Twilight’s vagina. Almost at once, Rarity resumed her powerful thrusting while continuing to urinate strongly. The previous squishing sounds were now replaced by splashing as with each deep and powerful thrust of Rarity’s hips a spray of glistening yellow pee was forced out under pressure around the unicorn’s shaft to splatter over her balls and back legs.

This new and rather unique sensation and the feeling of having her body being so wonderfully violated by the waste of another mare was enough to make Twilight cum with a cry and a spray of clear fluid that mixed with Rarity’s yellow.

Rarity made sure to hold on to Twilight’s hips to keep her penis in place as Twilight wiggled and pushed against her crotch while she came. Finally, with a moan Twilight slid herself off the penetrating organ and slumped to the floor breathing in gasps while an interesting mixture of fluids leaked out of her pussy.

Rarity, managing to remain standing, watched Twilight with a mixture of love and prideful satisfaction at her ‘conquest’ while fetching her very messy diaper off the chair she had laid it on. With carefully practiced magical manipulation Rarity eased the poop smeared and pee filled disposable diaper up between her legs and back over her cock and balls, then up over her butt. Once secured firmly back into place she pulled the tapes tight and pressed them down, re-sealing all her sensitive parts back within the warm and slimy confines of her bulging diaper.

Getting back to her feet proved a bit of an effort, it was awfully nice down there on the cold floor, but the whole point of going out of her way to see Rarity was to have great sex and have it fast. Lazing around would only serve to negate her advantage.

"Thank you so much Rarity, that was wonderful, just like I knew it would be.” Twilight said before giving Rarity a quick kiss on the lips.

“Mmm, pleasure’s all mine, not every filly’s lucky enough to get to do that with a princess.”

“Not every princess is lucky enough to have a mare with a diaper full of poop so ready and willing.”

“That’s not true, actually.” Rarity said dryly.

“Right well, I’m still lucky…” Twilight said awkwardly.

“I’m sorry Twilight, you’re just too much fun to catch off guard.” Rarity said leaning her head on Twilight’s shoulder.

Twilight couldn’t help but quite keenly feel Rarity’s diapered hip on her own bare one.

“I guess since you already have your diaper back on it would be too much trouble to remove it again and let me suck you off or something… But I do wish I could do a little to repay you before I go.” Twilight said.

“Well, to be honest I was going to say that being able to cum inside a princess with a poopy dick was its own reward, but now that you mention it…”

“Here, if doing things quickly is the theme of the morning, then let’s try this.”

Rarity once again undid the tapes of her diaper, but she did so while remaining standing so that the front of the diaper, underneath her in this position, opened and hung down between her back legs. Twilight watched the glistening layer of poop spread around the inside of the diaper to see if it was going to immediately start dripping off onto the floor. The consistency was such, similar to slightly too wet peanut butter, that this did not happen, though Twilight figured that a few minutes in this position might prove sufficient.

Rarity seemed to have come to the same conclusion.

“Well, better get a move on shouldn't you.” Rarity said, prodding her thick black cock at Twilight’s lips.

Having been placed back in the diaper for a few minutes it was once again just as poop smeared as before Rarity had done her best to clean it off inside of Twilight.

Twilight decided that hesitation would get her nowhere under these circumstances and so she opened her mouth wide and slid her head forward at such an angle that Rarity’s wide glistening length was lined up with her throat.

She felt her gag reflex grow quickly stronger, but her experience and mental control over her body allowed her to overcome it just as fast.

Rarity grunted with pleasure and began to throat-fuck Twilight, pumping her slimy shaft in and out as far as she could go, causing her open diaper to swing back and forth between her spread rear legs.

The poop that had been on Rarity’s penis was now doing an equally good job of coating the inside of Twilight’s mouth. If Twilight was honest she’d say the taste was not great, mostly bland and a bit bitter. But taste was hardly the point. It was the feeling and the texture of everything in her mouth that she loved, and she swallowed as often as she could.

All the subtle indicators, the more frantic breathing and pumping, the grunts and moans, and the taste of pre-cum all told Twilight that an eruption was eminent.

As predicted, Rarity curled a foreleg behind Twilight’s head and pressed her forward so that her muzzle was pressed into Rarity’s shit-smeared balls as the unicorn came for a second time like a fire hose, straight down Twilight’s throat, where she could feel the hot cum splatter around inside her neck.

Gaging slightly as Rarity removed herself, this time from Twilight’s other end, Twilight tried her best to steady her breathing as she swallowed anything left over in her mouth.

“Thank you Twilight dear, I really did need that. Cumming once around you is never enough, I should have learned that by now.” Rarity said as once again, she taped the thick disposable diaper back over her erection, allowing the diaper to hold the shaft firmly in place so it could soak for hours yet to come in the warm squishy darkness inside Rarity’s discolored and bulging diaper.

Chapter 2: The First Primitive Experiments

Author's Note

Apologies all around for taking so long to get this published. I started writing this chapter back in um, March, I think. but my professional life tends to take over for long periods of time and honestly, my interest in MLP has wained some for me this year as well, at least so far as the show itself is concerned. But fortunately for you all, I still enjoy writing about ponies doing naughty things in diapers. Some might be disappointed that this chapter is not as hot and heavy as you might have come to expect from me, but I wrote this to help set up the events in upcoming chapters. If I'm going to write about diaper transformation, I want it done right, which means lots of background concepts and scene development. Also I would like to comfort my readers by promising that this story will not get onto any dark subjects or storylines, as some diaper transformation stories (and images) often do.

Chapter 2: The First Primitive Experiments

When approaching Canterlot Castle on days like this one where thick banks of grey clouds hung low over the valley and obscured all but the foot of the great mountain range whose lower slopes play host to the tiered city of Canterlot, the sense of mystery and hidden grandeur of the ancient castle always managed to excite Twilight. No matter that she had practically grown up there and used it as nothing less than a second home for many years.

The choice to have the castle built on a wide ledge separated from the valley floor by high cliffs of hard granite stone five hundred meters high, and placed next to a powerful foaming cascade, had been one of the most daring architectural decisions made in Equestrian history. Yes, there were a multitude of ancient castles and keeps, many now little more than tumbled ruins, some still inhabited by the descendants of once powerful noble houses that occupied even higher mountain peaks than this Castle, but none of them held a perch that was quite so…dynamic in its character.

Flying in a wide downward curving arc, Twilight partially circled the castle’s highest towers, which appeared and disappeared behind veils of mist and occasional sheets of rain. For the inexperienced, a quite dangerous thing to do, but Twilight knew exactly where she was in relation to the pinnacles of finely crafted white stone with only a fleeting glance of a specific spire or window seen through the scuttling clouds to guide her.

As she spiraled in, a group of four pegasi guards on patrol swooped in quite close to her as she approached near the highest of the towers making sure that nothing dangerous was attempting to sneak towards thoes they were sworn to defend. Seeing it was Twilight who was soaring in and out of view they snapped sharp coordinated salutes and banked hard up into the clouds, disappearing again in their constant vigilance for invasion, be it obvious or subtle.

Twilight couldn’t suppress the stray thought that even had the guards wished to stop her, there was nothing they could have done. Ten times their number would have been unable to resist the power she could bring to bear.

“One princess is an army, and as such needs to behave with all the combined honor and responsibility of any thousand solders of the Royal Guard.” Something that Luna had told Twilight in a private conversation a few years back. Twilight had thought it a slightly harsh bit of advice at the time. Though since Luna had lived most of her life during a time when the Royal Guard had been rather less ceremonial than it was today, Twilight supposed it was simply Luna’s version of good wisdom, and not meant to be overbearing.

Landing as lightly as possible on the semi-circular balcony perched near the top of one of the taller towers, Twilight folded her wings down and shook herself a bit to rid her fur of the water droplets clinging to it while walking below the awning of the conical roof.

The gilded glass doors were standing open, just wide enough in fact, to admit a Twilight sized pony, the sign of expert castle servants, Twilight knew.

She slipped in, hooves finding themselves on a plush and intricately woven rug of blue and bronze colored thread.

Nopony other than herself was to be found within the ornate stone chamber. Though somehow the room managed to appear quite cozy with its thick stone walls and large fireplace, despite being a good hundred fifty meters above the castle’s court yard below. Twilight never knew quite what to make of that, a cozy room should be near to the ground, not perched up here like some griffon nest. The dichotomy of impressions was simply odd.

Being careful that her saddlebags didn't knock into anything delectate or otherwise make a sound, Twilight trotted, unhurried, around behind the large, ancient wooden desk that had been set up for her. Its polished Rosewood paneling depicting carved scenes of various great events in Equestrian history.

Twilight had requisitioned this room, and the desk, among other various effects of state for her temporary office while the restoration of Everfree Castle was proceeding. If all went to plan she would be able to move in permanently in only a few years, quite a short time considering that the only original part of the castle to really be salvageable was the stone walls, and even those had suffered damage and collapse in a few places. Fortunately, Celesta had seen no problem in granting Twilight the use of this tower as her headquarters in the capitol for the time being. And the large bay windows across the room from her desk did have quite the magnificent view. When it wasn’t cloudy and drizzling rain that is.

Though sighing at the rivulets of rain water on the window glass, she nonetheless felt content. Her morning had, after all, hardly been without its pleasures, and despite the beginning of a new week of responsibilities, she was sure to work in more fun for herself and friends.

Placing her saddlebags to her right behind the desk she hopped up into the wide padded chair, another nice piece taken out of the storage rooms, its wood so dark it was nearly black.

Settling in to her work Twilight ran her eyes over the assortment of documents spread around the surface of the desk. Some had been there since last week while others had been delivered by the Head Butler since she had last been in this office, a delivery only a master servant had permission to carry out as only a pony with a lifetime’s loyal service could be allowed to enter the offices of royalty unwatched. There was a transfer of funds form that would approve the transfer of 3.6 million bits to the Everfree Castle restoration project from the Lunar Bank, enough for the next 6 months of work. A petition for further land grants to the Lord and Lady Trumpetvine in the north-central foothills of the Unicorn Range. Twilight scowled at this, judging from similar past petitions, they were hoping to build another summer lodge in the area and wanted it to be on as much property as possible. Twilight decided she would be pleased if she could find some way to deny them. The aristocracy should deserve what the crown provided by doing good works for the nation, not have gifts heaped upon them simply for existing. If that were not enough, the very fact this petition was on her desk and not Celestia’s indicated that the Lord and Lady knew Celestia would have none of it, and were hoping to bypass her authority by going to Twilight directly. An unfortunately common occurrence these days. Another letter buried near the middle of the stack though, made her smile when she saw the cream-colored envelope with red accent lines drawn about the edges. Addressed to her from a certain Dr. Oldstone, it was sure to be his monthly update on the progress of the archeological digs in the Central plains north of the Unicorn range. She was tempted to open it immediately but forced herself to be patient, there were a few dozen more practical if boring documents to attend to first and it would not do to be distracted.

No sooner had she thought this though, then she looked at another letter, the last one in the stack, as the light lavender color of the envelope caught her eye.

It was addressed to her from Moondancer.

Not such a surprising thing as it may have been a few years ago, now that their friendship had been rekindled, yet hardly an everyday occurrence. This time Twilight had not a clue what it could be about, and decided that if Moondancer was experiencing some problem, it would not do to delay reading… whatever it might be.

A quick flick of power from her horn opened the envelope atop her desk and she unfolded a plain white sheet of paper upon which a short message was written is small but well-formed letters.

Twilight,

I have a special project I’m working on, it involves both diapers and magical expertise, two things I know you have lots of. I’m sorry to bother you with this, I know you are a busy pony, but though there are ponies who enjoy diapers and ponies who are magical experts, aside from myself, you are the only other pony I know who is both. I don’t want to tell you what I am working on in this letter because my idea is a bit well… odd, and I want to run it by you in private. That, and I’m kind of stuck, I’m not sure how to make progress on my idea and I think you are the only pony who can get me, well, un-stuck. Could you come to my house as soon as you get the chance?

Thanks!

- ‘Dancer

Twilight couldn’t completely prevent herself from groaning.

Diapers. Why did it have to be diapers? Would this fetish consume her life? Sure, she loved diapers and her experiences with them, but she was supposed to be a responsible mare, and here they were intruding into her professional time. And now of course, she was thinking of them again, which began the stirrings of excitement in her body. After all, Rarity was more than likely wondering around her boutique in the same used diaper she had been in this morning knowing her. And Moondancer herself was probably in one too, after all, a mare who rarely left her house was not often required to not be in a diaper, and Celestia knew what Flutters and Dashi had gotten up to after Twilight had left this morning. Perhaps Applejack was- no! She would not think on it!

Twilight pushed the opened letter under the nearest stack of papers and vowed she would not so much as think on it until she had taken care of everything of legitimate importance on her desk even if it took until after sunset. This thought, of course, prompted one of the master servants to knock on her door, announcing the delivery of a new set of documents and letters.

* * * * *

The sun was indeed setting behind the pointed rooftops and spires of the homes, inns, and shops to the west. Its golden light casting long shadows across Twilight’s office as she yawned and picked herself up off the chair. Fortunately, documents had not truly been the only thing to look forward to that day, a few journeys down to the throne room, to three of the greeting halls, and a walk in the north garden with the mayor of Baltimare had added some spice to her day, and a bit of exercise as a bonus. But despite being extra productive, even by her own standards, Twilight was happy to be done. At least for now.

Well, done with responsibilities that is. Tucking Moondancer’s letter into her saddlebags, incidentally next to her folded up morning diaper, Twilight trotted out of her office and onto the balcony. She was pleased the rain had cleared up by the early afternoon so she would not arrive at Moondancer’s house dripping wet. She supposed she could teleport, but Celestia had long ago told Twilight not to overdo it with that ability, as it was not always as practical as a pony might first think, not to mention potentially quite dangerous if the intended destination was not directly in sight.

A leap, and wings spread wide, sent Twilight soaring down among the lower spires and out over the ornate mansions and luxury hotels tucked up as close to the Castle’s walls as they could get. The closer to the seat of government a pony lived the more expensive it was to reside there. But this circle of great wealth was not Twilight’s intended destination. Moondancer was not the wealthiest of ponies, and would be hard pressed to live near Canterlot Castle even if she wished, but she seemed quite content with a modest older house near a public park on the north side of the city, an area with plenty of open green spaces and not nearly so cramped as the inner districts. Even if the surrounding buildings were often still larger than Moondancer’s home. The neighborhood was quiet and peaceful, well suited to a pony who preferred to go undisturbed for as long as possible. This was probably why Moondancer remained less financially well-to-do when compared with many of the ponies Twilight had spent her fillyhood around in the center of the Capitol. Any position of great authority and responsibility, specifically thoes which Twilight herself had offered Moondancer would inevitably lead to Moondancer being, in her words, “Endlessly bothered by ponies who have no respect for my own peace of mind.” The pony was a brilliant scientist and magician but remained determinably uninterested in much outside of her own research, the thought of holding high government office, which Twilight knew she would be good at, disgusted her.

Twilight spotted the familiar residence from the air, its peaked red tile roof and dark stone chimney still illuminated in the setting sun. Spiraling down, she landed within the low stone wall surrounding the front garden with enough grace to make Rainbow proud and trotted to the door wondering just what it was she was getting herself into this time. The previous summons from this mare had resulted in an incident involving a standing energy matrix which had enlarged a pile of blueberries and raspberries to the size of beach balls whereupon they had promptly dissolved into a fine dry powder coating everything within the house. Cleanup had taken hours, and dissuaded Moondancer from applying the energy construct to a living subject.

The deep violet stained door set in a dark yellow frame and surrounded by white washed plaster walls was something of an odd combination, but at least the exterior had been repaired and cleaned since Twilight had brought the mare out of seclusion a few years back.

As Twilight was near to tapping her hoof on the door it unlocked and swung inwards, with suspiciously perfect timing and apparently of its own accord. Twilight smirked to herself, considering the effect unnecessarily dramatic. Couldn’t the mare just come to the door like a normal pony? Then again, hoping Moondancer would do something simply because most other ponies would do it that way was a good way to waste time.

A voice called to her from somewhere further back in the house.

“Hey there Twilight, come on in, glad you could make it. I’ll be there, just a sec…”

The interior of the structure always seemed to be a little too large with perhaps a few too many rooms to be accounted for by the exterior size of the house. Twilight suspected that if Moondancer had in fact perfected metric expansion or dimensional folding to this degree, she could use it to become the wealthiest pony in Equestria, but again doing so would interrupt her continued research and so would probably never happen. Smiling, Twilight again found herself thankful to know a pony who was so honest about what she wanted out of life and had no care for money and power. Quite the opposite of many Twilight was forced to deal with in her daily existence. Herding angry deceitful cats simply wasn’t in it.

True to her word the mare in question soon came through to the narrow entry hall from further back in the house after Twilight had pushed the door closed and set down her saddlebags, happy to be temporarily rid of the burden.

Moondancer’s characteristic shy smile only ever seemed to be emphasized in Twilight’s eyes by her thick eyebrows and glasses. A combination that for some reason left the young alicorn always feeling more relaxed, as if no pony who looked like Moondancer could possibly cause Twilight any stress. A rare feeling indeed, and odd considering the process of renewing their friendship a few years back had not exactly been the smoothest of affairs to begin with. But, there it was, and Twilight was not about to complain.

“So, I assume you got my letter, I’m glad you got here when you did, I’m not sure I could have waited patiently even one more day for you.” Moondancer said while hugging Twilight and giving her a quick kiss on one cheek.

“If you were that impatient about it, you could have gone straight to the castle. They know you there and would have let you come right to me, no delays.”

“Ugh, and deal with the guards, and the clerks, and a master servant or three? No thanks, this way, I never had to step out my door!” Moondancer replied.

Again, Twilight was amazed at the lengths this mare would go to if it meant avoiding contact with the rest of ponykind.

“I see.” Was Twilight’s simple reply, delivered with a touch of her long-suffering patience for the quirks of her friends.

At least Moondancer had the sense to look slightly abashed.

“So, you’re doing something that involves diapers then? Something you want my input on?” Twilight said getting to the point. Twilight hoped her somewhat deadpan tone was enough to hide the fact that she was beginning to feel some excitement over whatever it was Moondancer was cooking up this time.

Twilight also used her inquiry as an excuse to openly acknowledge the disposable diaper Moondancer was wearing with a pointed stare, though nothing in Twilight’s look held surprise. She had figured Moondancer would be diapered from the start of their meeting, owing to both the subject of the letter and the fact that Twilight suspected Moondancer rarely spent any great amount of time out of a diaper. The only major exception to this was the library, as that was a place that frowned deeply upon any form of distraction to its patrons, up to and including bad smells.

The same kind of smell, incidentally, that had greeted Twilight upon entering the house.

“Oh yes! I’m sure you’ll find what I have to show you to be very interesting…” Moondancer said in a slightly mysterious manner, turning to the side and nodding her head towards the back of her house.

As she turned, her diaper came more into view for Twilight, first exposing the side, so that Twilight could see it was both thick and well made, there was even decent padding over the hips.

The plastic backed disposable diaper was mostly white but was randomly and liberally speckled with light lavender six pointed stars. Twilight’s eyes narrowed a fraction as she considered that thoes stars seemed suspiciously like the ones comprising her cutie mark, even if the color was a bit off. She had always thought diapers printed with a pony’s cutie mark was a good idea, and somehow, she was not surprised to see Moondancer attempting something similar. Always was one for experimentation, that mare.

Completing her turn and walking off down the hall, Moondancer kept her tail raised, providing Twilight with an un obstructed view of the back of the diaper. The diaper was not as white as it once had been however, the entire back and as much of the crotch as she could see was stained darker than the padding over the mare’s hips. And too dark to be accounted for by pee alone. That diaper was full of a big squishy mess and it was beginning to make Twilight a little envious. Though she steadfastly kept her mouth shut as she followed the pony in front of her to the top of an old wooden stairway leading down near the back of the house. If Moondancer wanted a reaction out of Twilight over her choice of underwear, she was going to have to work harder than that.

Her insistence on remaining silent did little to reduce Twilight’s enjoyment of watching Moondancer’s butt and hips move inside her diaper as they made their way to the bottom of the stairway with old boards creaking under every light hoof fall. Ponies often seemed to think wearing a used thick diaper would result in a humorous waddling walk, but it was Twilight’s experience that this effect only ever occurred the first time a pony wore a diaper as an adult if even then. Anypony with even a modicum of experience with diapers tended to walk quite normally, no matter how full their diapers became. Of course, waddling could be forced by more extreme measures such as wearing multiple diapers at a time. But Twilight had no interest in doing so. Twilight had decided long ago that the cause for this was two-fold. On one hoof, if the pony in diapers was so used to being in them that she was no longer paying attention to it being on her, she tended to revert to a natural walking movements. The other extreme seemed to be that when ponies, herself included, became turned on by wearing and using a thick diaper, she preferred consciously walking normally as that forced the diaper to press and rub even more strongly against her inner thighs, and caused the diaper’s contents to squish around in the most wonderful ways as she walked. In her opinion, The true test of a high quality disposable diaper was that one at a time was enough. If a pony wore a good quality diaper in the first place no regular days’ worth of wetting and messing should be able to make the diaper leak badly enough to warrant a second diaper to be put on over the first.

Twilight enjoyed her musings on diapered pony behavior at just about any time, but even more so when a cute diapered mare stood just in front of her.

Having reached the bottom of the stairs, Moondancer continued her steady pace across a clean floor made of irregularly shaped, but flat slabs of dark grey slate fitted crudely together and with aged, crumbling mortar filling the many gaps where the stones did not mesh well. The floor combined with the rounded river stone walls made the clopping of their hooves sound louder than they had upstairs when surrounded by so much old wood and even older rugs and wall hangings.

Moondancer stopped in front of a low but long wooden table set up against the far wall of the dimly lit room. With a quick flash from her horn two bare lightbulbs on chains glowed to life above them.

Twilight was familiar with the room itself, she had stood in it on several occasions over the last few years, and while she could recognize many of its contents, more than several items were new and what was familiar was now in un-familiar locations. Moondancer did seem to enjoy a seemingly constant process of shuffling things around as if playing a never-ending game of maximizing the usefulness of a room and its contents through careful positioning.

Twilight found herself somehow unsurprised to see a series of disposable diapers laid out on the table, more a workbench she decided after a moment’s consideration.

“So, uh, before I tell you about anything here, would you like to be in one yourself? Moondancer asked.

Twilight had no need to ask what it was she might want to be in.

“Oh, why not, I think I will. I was in one this morning, might as well be in one for the evening too.”

Twilight did her best to not let her excitement show. She had not wanted to come right out and ask to be diapered herself, and didn’t want Moondancer to think of her as nothing but a horny filly waiting on the smallest excuse to jump into a diaper. But now that Moondancer had asked, she could finely be diapered without appearing to lack all self-control.

This was also the reason why Twilight didn't bother to mention the wet diaper tucked into her saddle bag from her morning activities, if she admitted to having that and then went back up the stairs to put it on, it would look like she had planned the whole thing out. No, Twilight wanted her acceptance of the diaper to appear as casual and spontaneous as possible. Within certain circles, Twilight was already known to have a diaper fetish, she saw no reason to add a reputation for being desperate to engage in that fetish. She was, after all, trying to work on her image of being a proper princess, even if a good book made her forget herself all too often.

“Cool!, well then, here you go.” Moondancer said, levitating a still folded but obviously thick disposable diaper over to Twilight from a stack of them in a dusty wooden box near her side of the bench.

Despite the state of the box it came out of, the diaper itself looked pristine, no dust at all, and the plastic outer layer and padding was in perfect condition, no creases, lumps, or tears. The diaper was mostly white except for pink accents around the leg guards and small tail hole, a single wide pink stripe running down the middle of the diaper from the top of the front to the top of the back, and four pink tapes. These tapes Twilight pulled on tightly while pressing them firmly down in place onto the thick plastic of the front of the-, her diaper.

She sighed a little to herself as the warm, thick tightness of the diaper settled around her. Even unused it felt nice and comfortable on her body and it pressed against her crotch and butt in so many wonderful ways. She was a little disappointed that she didn’t have to go potty right there and then, but not even a princess’s timing could be consistently that good.

Her attention returning to the present, Twilight blushed a little as she caught Moondancer’s knowing smile, a smile that told how Moondancer knew exactly what Twilight had just been feeling as she had taped on her new diaper.

“These are nice diapers Moondancer, where’d you get them from?”

“Oh, well, there’s this pony named Rarity who owns a successful clothing company, which has a not so well known division specializing in diapers…” Moondancer trailed off grinning.

“Ah, of course, Rarity does rather dominate in that market segment around here doesn’t she.” Twilight replied.

“Seems like it, you know, her diaper store is not that far from here, we should visit sometime, you and me. I go there every now and again to buy a box or two of various diapers. I like to try out different styles. The one you are wearing is a little on the plain side compared to some of the styles I have seen there, but they are made very well and I think a simple design is often best, besides, it's the mare that makes the diapers look good more than the other way around.”

A short awkward silence followed that statement as Moondancer realized how her words betrayed her thoughts on Twilight’s diapers and the mare herself.

Turning back to the workbench and the diapers laid out on it, Twilight gestured with a hoof to them, attempting to rescue her friend from embarrassment by bringing Moondancer back to the original reason they were both still down in the basement.

“So, about these…?” Twilight began.

“Ah, right!” Yes, well…” Moondancer took a deep breath and adjusted her glasses.

“That diaper in front of you, that was one of 48 I bought as a custom order from Rarity a few weeks ago, I had seen Rarity wear diapers based on herself like that, and thought it would be fun to do the same.”

The disposable diaper laying in front of Twilight that Moondancer was discussing, though still folded up like it had just come out of its package, was obviously quite thick and made with good strong but soft and smooth plastic. The unique thing though, was that its color was a light tan, that perfectly matched Moondancer’s coat color and, if that was not hint enough, the mare’s cutie mark was printed boldly in the center of the diaper. Twilight had noticed this, as soon as she had gotten close enough to see the diaper, but had wanted to wait to hear Moondancer’s explanation when she chose to give it.

“So, I wore thoes, for a while, and enjoyed them quite a lot. Being in a diaper based on my own body was rather, um, exciting.” Moondancer giggled a little at this, but went on.

“But that got me thinking, if wearing a diaper that looked like me was fun, wearing a diaper that looked like another pony, that might be even more fun.”

Taking a deep breath, Moondancer moved over a bit allowing Twilight to stand in front of the second diaper laying on top of the workbench. This one she smiled at even more.

“So, I ah, had these ones made, I hope you like them. I sure do…”

Twilight stared down at another diaper that was made identical to the first but the color was now lavender, and the cutie mark printed boldly on the front was her own. She was even more sure now that the used diaper Moondancer was currently in was based off her cutie mark, if not in quite so direct a way.

Twilight raised an eyebrow, but seeing the nervousness on Moondancer’s face, she softened her expression.

“I’m flattered Moondancer, I really am. I’m glad you like me enough to have had these made.”

Twilight gave Moondancer a quick hug to show she really did mean it, and enjoyed how her diapers felt and sounded as she moved herself. She also got a fresh whiff of the smell coming from inside Moondancer’s diaper and privately enjoyed that as well.

“Anyway, um, wearing diapers based on how my friends look… well, I started to daydream about how it would feel to ah-“

Moondancer paused, and adjusted her glasses again looking at the floor.

“Well, I thought it would be an interesting experiment to-“

She paused again.

“What I’m saying is that instead of just wearing a diaper that looks like me, what if I, well, was that diaper… or at least could feel what that diaper felt, if well, it could feel anything at all!” Moondancer finished in a rush looking more embarrassed by the word.

In the following silence, Twilight blushed but spoke comfortingly.

“Don’t feel strange about it. I think I might have had that fantasy once or twice myself. Probably many ponies in diapers have had such a notion cross their minds at least once.”

“I- thank you, yes, well about that. See, I thought, well, I thought I might actually be able to make my daydream come true, at least to an extent…”

Moondancer said gesturing to the third diaper in the row.

Twilight’s earlier feelings of pleasant amusement and slight arousal were suddenly being replaced with curiosity and a vague sense of unease.

The third diaper in the row was more standard than the previous two, it was in fact the same design at the one Twilight was now wearing, but instead of pink accents, the leg guards and stripe were light green. Another difference was that this diaper was quite soaked.

“When I wore this diaper two days ago, I attempted a standard psychosomatic transference spell, but modified so that only my interpretation of sensation was translated to the diaper without the usual accompanying physical or visual manifestation occurring in the object being projected into.

Leave it to Moondancer to describe a PT spell as ‘standard’ when thoes sorts of things were only performed by Unicorns with a minimum of a decade of magical training behind them. To say nothing of custom, on the fly modifications.

Moondancer continued her story though, and Twilight listened with interest.

“The experience was certainly unique, I could feel myself as the diaper I was wearing, but not completely, it was like a secondary alien sensation overlaid on top of my natural body image. In of itself not surprising, given that this is common for such spells, but as this type of magic is typically used where the object being manifested into is already pony shaped, a doll, or figurine, or as an image of a pony on a page, thanks for that idea by the way, the… discrepancy between the pony’s true body image and the object or image being projected into is usually minor. But projecting to a random object like a diaper that shares no resemblance to the physical form of a pony… well, I had a headache for several hours afterwards and had to lie down for a while to recover. But the other problem is that these sorts of spells do not allow for a pony to operate her own body throughout the casting. It’s generally advised to be laying down when performing a spell like this as the mind can only concentrate on existing within the object being projected into. In this case, it meant that as soon as I was projected into the diaper, I couldn’t do anything anymore, not so much as twitch an ear. Interesting at first, especially, when I uh, wet myself, in an oddly literal sense, as I no longer had any bladder control. But I couldn’t feel my own body very well, and I couldn’t move. Interesting at first, but it got boring quite quickly.”

Twilight, was reminded again that this pony could have become a respectable lecturer at Canterlot University, if she wasn’t so determined to keep to herself as much.

“Well, that certainly is interesting, a little dangerous to try on one’s own perhaps. Though truthfully, I almost wish I had attempted that sort of thing myself.”

Twilight hadn’t done so because she had guessed that the sort of unpleasantness Moondancer had suffered might result from her own attempt, but she said none of this to Moondancer. At least the pony had been persistent enough to have gone and tried it.

“Yes, I agree, but you see, I realized that there was no need to stop the experiment there. I may be limited in what I can do myself, but with a second pony helping me, who knows what we might be able to do!”

Ah, Twilight thought, I think I know why she went out of her way to ask me to come here.

The unabashed enthusiasm on Moondancer’s face seemed a little at odds with her usual attitudes of either being shy or in lecture mode. What it meant to Twilight, was that there would be no easy escape from Moondancer’s plans, whatever they were, and Twilight was not sure she even wanted to escape in the first place. Diapers were involved after all, and that was a big attraction for her, in more than one way.

“I see, Twilight said a little cautiously, I assume you have an idea of what to try next? I hope it’s nothing too dangerous.”

“No no, nothing too weird.” Moondancer paused for an instant and Twilight could almost feel the unspoken “yet” in there, but she kept silent again.

“I want to go up to my bedroom so we both have something to lie down on.”

Twilight raised her eyebrow again, and Moondancer blushed but hurried on.

“I want for us to take turns projecting our consciousness into each other’s diapers but not at the same time. That way I can experience how it feels to be a diaper on you as you wear and um, perhaps use me. Then after a while, you can do the same with my diaper while I wear it. This way we can both experience being a diaper on an active mare, and not on one incapable of moving. Also, hopefully, being a diaper on another pony instead of one on yourself will help to reduce the weird mental feedback issues so the headache will be less. If not, this time I am prepared with a healing potion so we won’t suffer for long.”

Twilight was not sure of this proposal, but Moondancer had obviously tried it with little trouble and frankly, the idea was beginning to turn her on, even if the experience was sure to be rather odd.

“I, well sure, I wouldn’t be much of a scientist if I refused to experiment. Let’s try this out.” Twilight said doing her best to not be nervous.

Chapter 3: Slightly More Advanced Experiments

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