Sweetie Belle's Magical Mistake: Swapped Bodies and Soiled Diapers

The sun was just beginning to dip over the horizon as it cast it's brilliantly changing colors across the landscape of Ponyville. The vibrant colors of the evening sun bathed the surrounding area in a tranquil blanket of serene beauty as most creatures began to settle down for the night to come. The same somber calmness reached across a large tree house as it did with every other structure in the area, only to be shattered by the sound of light explosions and rattling objects as the occupants of said tree abode were long into a session on the merits of using magic correctly. The light that poured in from outside, like a caramel coating over the wood sculpted interior, was quickly cut aside as flashes of magic changed the lighting within. There in those ever changing lights stood three, two unicorns, a small white filly with lavender and pale pink locks, and a surprisingly white diaper, known as Sweetie Belle. The other, a lavender mare with mane of purple that had a pink streak through it by the name of Twilight Sparkle. Off to the side stood a small purple dragon adorned with green spines, and a slightly yellow stained diaper around his waist. All three of them looked to be generally exhausted, from any number of things that came with the rigors of training ones magical talent.

"I know we've been at this for some time Sweetie Belle, but I think you'll get the hang of it." Twilight stated.

Sweetie Belle's only response was to groan out loudly while stamping her hooves against the floor. Twilight looked around with a slight slump to her stance, looking at all the books that were strewn around and the overall mess that would need to be taken care of. While that was going on, a knocking came from the door to the library, to which Spike quickly waddled his way over to and opened it up, revealing none other that a white mare with an elegant purple mane.

"Oh hello Rarity!" Spike exclaimed excitedly as he held the door open, bowing his head slightly and waving his arm back in an elaborate manner to welcome Rarity inside.

"Thank you Spike." Rarity said as she came in. "I don't suppose the training has been going particularly well?" she continued after seeing the state of things.

Twilight shook her head. "Oh no, I feel like we've made some real progress today, Sweetie Belle was just trying out a spell to change the color of her mane." the mare explained.

"Well I suppose it'll have to sto-" Rarity was cut off by.

"No! I can do it! Please, just one more try before we go!" Sweetie Belle exclaimed with a high pitched whine.

"Sweetie Belle, I know you want to try to progress as quickly as possible, but sometimes you need to know when to call it a day. Besides, I'm sure Twilight would love to be finished so she can clean up and get a bit of rest." Rarity went on.

Sweetie Belle immediately found herself turned towards Twilight, eyes wide as she looked up at her mentor, of course it didn't take more than a moment for Twilight to wither under such a look.

"Oh it's fine Rarity, one more try couldn't possibly make this." Twilight gestured to the room with her hoof. "Any worse than it already is." she finished.

Rarity rolled her eyes for a moment. "Oh very well, but only one more try Sweetie Belle, we don't want to put off dinner any longer than we need to." Rarity stated

Sweetie Belle bounced in place as Spike went ahead and shut the door to the library, knowing better than to leave it open when Sweetie was about to try her magic. Spike headed back over to the far side of the room, as he passed Rarity, the mare scrunched her nose slightly at the scent of urine that she got a whiff of as he went by. Though before she managed to comment on it, her sister had gotten into a stance. Sweetie Belle was focused, she was ready. The filly began to charge herself up, magic building within her as she prepared to cast the spell. All eyes were on Sweetie Belle as the filly felt herself ready to try when something happened. Sweetie Belle could feel warm liquid splashing against her body, her diaper was growing heavy and wet as she urinated suddenly. A blush spread across her features, normally she wouldn't mind this at all, if it hadn't been for the fact that it was messing with her concentration and her sister was watching her. She was supposed to be using magic! Not wetting herself! Despite the lack of complete concentration, Sweetie Belle pushed ahead with the spell when things went wrong.

Rarity had been watching her sister intently as it seemed like Sweetie Belle had been building up to finally cast the spell, though she was immediately put off at the sight of her sisters diaper tinting a darker shade as liquid added to it and slowly the darker shade became a yellow discoloration. Rarity sighed as she realized Sweetie Belle was only going to accomplish making her diaper wet with all that exertion when the mare was suddenly blinded by an intense flash of light, and then she was out.

Twilight hadn't been paying much attention to Sweetie Belle as the filly did her best. Mainly she was thinking about getting Spike into a new diaper after this since she could see it from here and it looked heavy and swollen with how much urine it was currently holding, it was this lack of attention that caused her not to notice the sudden power surge Sweetie Belle had exuded. Completely caught off guard Twilight could do nothing to stop the blinding light from piecing her vision as she lost consciousness too.

Spike was just standing idly by, in case something happened where he'd need to move or perhaps move something out of the way, at the light from Sweetie's horn suddenly became intense, he realized something was about to happen, but he had little time to wonder that as he too felt his mind taking a back seat as he blacked out.

The sunlight that had bathed the place in a gentle glow was slowly dying away. Ambers and oranges began to fade into light reds and purples as the sun sank even lower into the horizon. Of all the creatures pass out on the floor, one began to stir. The dragon, it's limbs began to move spastically as it's eyes suddenly shot open and his cry pierced the still room. It was completely unintelligible, a mangled form of what could be considered language. In his flailing and gibbering, another form began to stir. Rarity. Picking herself off of the floor and into a seated position. The mare began to look around in confusion.

"What's go." was as far as the mare got before her voice seemed to just disappear.

'That's not my voice? No wait, isn't it? Why would my voice be, what voice?' thoughts raced within her mind as her eyes scanned the room

Rarity's eyes came to rest on the still form of her sister lying on the ground, the diaper that had been clean before was stained completely yellow by this point.

"Is that me?!" Rarity shouted.

It seemed to be true, Rarity was not the one looking down at her sister, but rather it was her sister who was looking down upon herself. Yes it seemed that somehow Sweetie Belle had put herself into her sister's body and vice versa. Sweetie Belle didn't feel much different. The only thing she could feel, was fatigue, but she assumed she would have felt tired now even in her own body! She had to do something, Twilight, she needed to get Twilight up too. Obviously something was wrong with Spike as well since the dragon seemed to be having some sort of fit on the floor. Getting to her hooves a bit unsteadily, Sweetie Belle slowly trotted over to Twilight, not used to being so far off the ground so suddenly, she reached the other unicorn and began to shake her.

"Twilight, you need to wake up! You have to fix this!" Sweetie Belle shouted.

The shouting and shaking seemed to do the trick, as Twilight began to stir as well, but she wasn't ready for the sudden hoof that came and hit her right in the jaw.

"Ow! What was that for!?" Sweetie Belle said, recoiling from such a hard hit.

But after she looked back over, she was horrified at what she saw. Twilight seemed to be flailing around on the floor, speaking gibberish and generally spazzing out. Much like Spike had been mere moments ago. Spike was now laying silently, Sweetie Belle had no idea what to do. She'd ruined everything and could feel the tears welling in her eyes.

"Rarity!" Spike suddenly shouted, grabbing Sweetie's attention.

"Spike?" Sweetie belle asked as she went over to the dragon on the floor.

Sweetie Belle looked down at the dragon, he seemed to be concentrating intensly as he laid there on the floor.

"Rarity. Not Spike. Twilight." was all Spike managed to get out.

Though it was all Sweetie Belle needed to hear in order to work things out.

"Twilight! I'm not Rarity, it's me, Sweetie, I'm in my sisters body!" Sweetie exclaimed.

Twilight looked somewhat perturbed by this, but it didn't stop her from continuing.

"Sweetie. Help. Need help." Twilight said.

"What do you want me to help you with?" Sweetie Belle asked her.

Twilight, in Spike's body, held up one claw and then pointed to her own body. "Help."

Sweetie went over to Twilight's body, which she could only assume was Spike, who had stopped convulsing and was just laying down now. Sweetie Belle righted the body, and laid it out on it's belly.

"Thanks." Spike said in Twilight's body, having gotten used to the change enough to speak properly.

Rarity got herself up and moved over closer to all of them as they were slowly getting used to things.
Twilight managed to sit herself up, wincing ever so slightly as she felt the sodden diaper squish against her scales. Realizing she was wearing Spike's wet diaper. Or technically, her wet diaper, in a way.

"Alright, so. Things have gotten a little out of control." Twilight spoke with Spike's voice, having gotten used to her body, it was a little odd hearing him speak in such a way, but that was hardly the strangest thing.

"A little!? Twilight our bodies have been switched, I don't know how this could be viewed as a 'little' problem!" Rarity exclaimed in Sweetie Belle's body, before bringing her rear down roughly onto the floor in a huff.. Completely forgetting she was in Sweetie's body, she felt her sister's sodden diaper squish warmly around her flank as her eyes went wide. "Eeuurgh!" she suddenly whined as she quickly jumped back up onto her hooves. "Oh this is disgusting!" Rarity exclaimed.

Sweetie Belle couldn't help but giggle at the situation, but said giggles soon earned her sister's attention.

"And what do you think is so funny! You are in so much trouble once we switch back Sweetie Belle!" Rarity shouted at her.

Sweetie Belle, despite being taller, felt herself withering under her sisters screams, her ears folding back as she turned her head away.

"Rarity!" Twilight exclaimed. "Fighting isn't going to solve anything right now. Not to mention if you continue to work yourself up like that you'll only cause yourself more headache for the moment." Twilight told her, being acutely aware of Sweetie Belle's body, she knew Sweetie Belle had a tendency to 'let loose' whenever she was nervous, or frustrated.

"Okay. Okay. Let's just all relax, and calm down." Rarity added, taking a deep breath and exhaling.

Twilight, Spike, and Sweetie Belle all decided to do it, mostly just to placate Rarity, each of them taking a deep breath, and sighing in turn, letting their bodies relax. Unfortunately, as Rarity let herself relax her tail subtly lifted up an inch, as a loud expulsion of air exited her rear end, making a horrifying spluttering sound as it echoed off of the inside of her wet diaper. Rarity's eyes went wide as she quickly assumed the worst, the other three also staring at her caused Rarity's face to light up like a bonfire before she quickly began to stare daggers at all of them as she realized, it was just gas, thankfully.

Sweetie Belle had been about to start giggling again when her sister's look changed, and although it was her face staring at her, she knew that look wouldn't mean good things for her if she let out even one little sound. Spike knew better than to say anything right now in regards to Rarity and was too busy trying to get himself upright, he'd managed to roll over onto his stomach at least, and Twilight quickly moved past it as she said.

"We need to get some things straight right now before we do anything else." Twilight said as she managed to sit herself up, feeling the wet diaper squishing around her scales, though the feeling wasn't terrible, not as terrible as she imagined it would be. "Those two, need diapers." Twilight continued while pointing to Rarity and Spike.

"What do you mean, they need diapers?" Rarity questioned.

"Well.. Spike and Sweetie Belle certainly aren't potty trained, and while they might have our bodies, they very likely won't recognize the right signals in order to.. Well, go to the bathroom." Twilight explained somewhat sheepishly, and once she'd finished explaining that, Rarity looked horrified.

"Absolutely not! I'm not going to have Sweetie Belle running about in my body wearing a diaper! Think of what everypony will say when they find out?" Rarity began to go on, only for Twilight to shout.

"Rarity!" Getting the mare's attention. "Would you rather that, or perhaps you'd enjoy hearing about the time you dropped a load of horseapples in the middle of Ponyville for the rest of your life after we've fixed this." Which was a statement that quickly ended Rarity's current complaints.. But not for long.

"Yes, but darling, how will we get them diapers? Perhaps we could slip Sweetie Belle's night diapers onto them, though they'd be stretched quite a bit by that." Rarity mentioned.

"I'm well aware, we'll likely need cloth diapers of some fashion." Twilight mentioned.

"Eugh.. It pains me to think of fabric being used for something so.. Filthy.. But I suppose if we got back to the boutique I might be able to do something.." Rarity said as she tried to light up Sweetie Belle's horn, finding it completely unresponsive. "Or.. Perhaps not.."

Twilight shook her head. "I doubt Sweetie Belle's body is going to be able to do any more magic for the rest of the day. Though that brings me to my next point. We need somepony else. As much as I would rather keep this under wraps, somepony is going to have to help us. Maybe Applejack or Fluttershy could work, but they're all the way on the other side of Ponyville.."

"Twilight you're not suggesting." Rarity began.

"Yes. We need to get Pinkie Pie.." Twilight finished.

"But who's going to go get her?" Rarity asked, internally dreading how much 'fun' Pinkie Pie was going to have with this situation.

"Oh! Oh! I can get her!" Sweetie Belle exclaimed as she bounced up and down, only to quickly be silenced by Rarity's loud.

"NO!- I mean, no, Sweetie Belle, you will stay right here."

"Yes, that is for the best. Rarity will have to go get her." Twilight stated.

"Why me?!" Rarity whined slightly as she turned her attention back to Twilight.

"Because Rarity, we can't let Sweetie Belle leave in case she has an 'accident' which would just get more ponies to notice her. Spike can barely move and I can hardly walk right now either." Twilight mentioned.

"Oh.. I suppose." Rarity said glumly as she got to her hooves, but before she could head away, Twilight called to her.

"Wait! You have to pretend to be Sweetie Belle until she gets here. Not that I'm entirely sure she'd believe you were you even if you told her, but I imagine you don't want to tell Pinkie then and there, since then everypony will know what happened." Twilight added.

To which Rarity nodded. "Right right. Wouldn't want anything like that happening." Rarity said as she began to trot off again. She could feel the wet diaper swaying slightly as she went, causing her to grimace slightly. Just as she reached the door another voice rang out.

"Wait!" This time it was Sweetie Belle. "Don't you want to get changed before you leave?"

Rarity frowned at the idea as she turned to face her sister. "As much as I don't enjoy sitting in your filth.. I was hoping to put off that little embarrassment for as long as possible." Rarity told her.

"But Pinkie Pie might try to change you if you show up in a wet diaper." Sweetie Belle mentioned.

A few moments passed as Rarity stood there, absorbing the information, before she asked. "Twilight, where do you keep Sweetie's diapers?" as she began trotting back towards them.

"On Spikes changing table." Twilight said.

"Sweetie come. You are going to clean up this mess you made, I will not be leaving until I am spotless." Rarity said as she trotted along past Sweetie Belle who just looked down at her sister with a sigh.

"Yes Rarity." Sweetie Belle said as she followed her sister upstairs.

Once the two of them had left, Spike looked to Twilight.

"So.. How do we fix this?" he asked, having managed to get his hooves under him now, but still laying on the floor.

Twilight sighed. "I'm not entirely sure, if I were in my own body I could begin casting some spells to see just what happened, but as we are, all I can do for the moment is hope that it's a temporary spell and it'll eventually wear off in a little while. Until I have somepony else we can rely on, that's going to be what we go with."

"Well, alright then." Spike said, and then continued. "Oh, and uh, sorry for when I eventually have an accident."

Twilight just shook her head. "Please Spike, it'll hardly be your fault at this point. Sweetie Belle might not know how to go, but at least she isn't working with a whole different species like you are." 'Not to mention different plumbing' Twilight thought to herself after her statement.

Meanwhile upstairs...

Sweetie Belle had picked up her sister and had laid her on the changing table, and unfortunately for Rarity, Sweetie Belle couldn't access her sister's magic, a few moments of sputtering and straining on Sweetie Belle's part had worried Rarity so much that she forbid her sister from trying to use magic while in her body. What was bad about that, was that Sweetie Belle would have to change the diaper, the old fashioned way.

Laying there as her diaper was untaped, feeling the cool air rush against her warmed fur, Rarity couldn't help but shudder as she knew she was going to be scrubbing her mouth out for days once this was all over as she watched Sweetie Belle pulling the wet diaper out between her teeth.

For the most part Sweetie Belle had thought this was going to be a neat experience, she'd never changed her sisters diapers before! Since her sister didn't wear them obviously, but it quickly turned into a sour experience as she caught the taste of her own urine as she grabbed the diaper in her mouth, tossing it in the nearby diaper pail as quick as she could, she got to wiping Rarity down. Thankfully the taste of the foal wipe took the taste of pee out of her mouth, but unfortunately, now she tasted foal wipe. It was rather awkward for her as she dragged her head across her Rarity's crotch and hind legs. Which in reality was her own body, which was odd to see from this angle to be sure, let along cleaning it!

Likewise it was just as awkward for Rarity, who wanted to not say anything during the change, but constantly found herself going. "You have to wipe inside a bit further Sweetie Belle, otherwise it's a health risk." or "Make sure you clean the fur properly, there should be no yellow stains! They show up really easily on your coat, goodness I think I'll need a bath though." What did end Rarity's rambling was when Sweetie Belle pushed the wipe into the filly's butthole, just a little, to make sure she was clean there, even though the diaper was only wet. A small shrill noise was the last thing Rarity uttered before Sweetie Belle moved on to sprinkling foal powder across Rarity's flank. After which she grabbed the new diaper, unfolded it, set Rarity into it, made sure to thread the tail through the back hole properly, then set about folding it up.

"Alright! Done." Sweetie Belle said as Rarity turned over and stood up on the table.

Rarity wiggled her flank and stretched her hind hooves. "I suppose you've done a good job here Sweetie Belle, it's fitting correctly, not too tight or too loose anywhere." Rarity commented as she hopped down from the changing table. "Now, I shall make my way to Sugarcube Corner. Hopefully once I bring Pinkie Pie here, we can get to work on getting this all situated."

Rarity and Sweetie Belle went back downstairs, where Twilight had managed to stand, somewhat shakily, while Spike had forgone trying to walk properly and was just crawling about, or shimmying himself along.

"So long Twilight, I shall be back as soon as possible." Rarity mentioned as she trotted to the door, opening it, and left, shutting the door behind her.

Spike and Sweetie Belle both looked at Twilight, whom found it odd to be staring at her own face as Spike looked at her. "Now, you two are going to the bathroom. Sweetie Belle you're going to sit on the toilet until Rarity gets back. Spike is getting in the tub."

Both of them looked annoyed, but offered no argument as Sweetie Belle attempted to help Spike get to the bathroom. As they went, Twilight idly rubbed the front of her diaper, feeling it squish wetly. She knew she was risking a diaper rash by not having Sweetie Belle change her, but she figured she could wait until Pinkie Pie got here, Twilight would deal with it, if it meant not risking watching Rarity defecate on the floor. A thought that made her shake her head as she unsteadily waddled after the two of them.