A Nightmare of a Masturbation Session

by bkill25

Rating: mature
Tags: Nightmare Moon, Porn, Fetish, Princess Celestia, Sex, Anthro, My Little Pony: Friendship is Magic
Length: 6743

Princess Celestia is tiny. Nightmare Moon uses her to rut herself (ruh-roh!)

Princess Celestia is tiny.

Nightmare Moon uses sister to rut herself (ruh-roh!)

Contains: Macro, boob-play, ass play, insertion, sisterly bonding?

Published 2018-02-12 00:20:06 UTC
Last updated 2018-02-12 00:20:06 UTC

Sisterly Bonding

A Nightmare of an Masturbation Session
ALT

“Is this really necessary?”

“Oh, yes.” Nightmare Moon smiled down at her prey, licking her lips as she did so. “Absolutely.”

From Princess Celestia's perspective, everything was utterly massive, from the sheets below her feet, the bedroom ceiling further than space itself, and, most important of all, the thick thighs that served as walls on either side of her. Try as she might, everywhere she looked had a part of her sister in her vision—and that thought caused her cheeks to flare pink.

“But I'm... too tiny to even hope to please you!” Celestia shouted up to the monolithic face of her partner, who grinned at the words. “Not only that, but your room is terribly cold, even more so when you're small and naked.” She cupped each breast and held them up. “My nipples are so stiff!”

“I'm afraid they're too tiny for my eyesight,” Nightmare replied, and the sounds of sheets shifting were heard. “Please, allow me to feel just how unwell you are.” And, just like that, Nightmare Moon began to slide her legs shut.

Celestia looked left and right, watching the walls of midnight blue thighs grow larger and closer, their meaty flesh promising some warmth to her shivering body. But she wouldn't have it. As the legs started to cross at the ankles, the princess of the day burst forward in a sprint toward her sister's crotch.

“You run, and yet, the results will forever be the same.” Nightmare watched as her 'little' sister ran toward her body, such a small creature utterly trapped by her body alone, completely under her control. “I...mmhmm...suppose that will of yours...oh yes...is what keeps igniting sparks in our subjects.”

Nightmare's legs were crossed at her knees now. The space before her crotch was shrinking by the second, but the miniature princess kept running forward all the same. This was her way of taking some modicum of control in the impossible situation, and to the giant, who possessed the real power, made it all the more tantalizing as she took it all away.

“Nightmare, you can—“ The wind was knocked out from Celestia as a force slammed into her back, followed by the plush sensation of fur. She sunk an inch into the flesh of the thigh as it flew across the mattress, right into the destination she'd been running to all along.

Her sister's pussy.

“You did not jest, dear sister.” Nightmare closed her eyes and stifled a moan. She'd captured the tiny woman with her inner-thigh and held it against her crotch, feeling her sister struggle against the lips of her pussy, which suckled on their treat with pleasure. “My nether lips feel just how cold you are. Shall I let you past my folds to warm you up?”

Something tiny beat on her mound. Nightmare's teeth tugged at her bottom lip.

“Mmmhmm, I do suppose you have a point.” Nightmare clenched the muscles in her thighs, pressing the tiny woman the hardest against her cooch, delighting in the tingling sensation to its fullest. “Sex is what we build up to.” She pulled her legs away. “A climax is only as good the work done for it.”

Nightmare looked between her legs to find a only puddle of her juices. She tilted her head, glancing along the length of her legs for her toy, when, suddenly, another tingling sensation shot up her spine.

“My oh my!' Nightmare giggled with delight as she fished her fingers to her pussy, spreading her lips apart. “Trying to get to the desert before you've had your veggies—and mother always called me the impatient one.” Her finger slid into her tunnel, not hesitating to flick her inner walls, feeling her nails come into contact with something even softer. “You'd have your fun, but it's time to come out now.” She pinched the softness and dragged it out of her tunnel.

Blackness.

Celestia saw only darkness the moment her body was pressed aginst her sister's soft, midnight blue pussy lips, beating upon them with her fist for any chance of escape, only for those same hand to fly past the folds and be sucked on by the muscles past. She'd begun to hyperventilate, feeling the fat of the thigh fill in around her, and before she could even know what was to come—it happened.

Luna's pussy pulled in her upper body while her column like thighs pushed her lower half in.

It was hot and dark in the tight tunnel, like a wet hug continually growing tighter around her frame with every convulsion, pulling her further into the passage. For Celestia, any attempts to be angry were squeezed out with every convulsion, which held her boobs tight and gave particular attention to her perked nipples. It was faint, but the juices welling around her burned at her own pussy in a delightful manner.

Before brought a hand to her own nether lips, patting them and moaning at the bliss, but before she could insert her fingers, she gasped as something gripped at her ankle, and a moment later, she was sliding out of the cave she'd just come to find pleasure inside.

The inner-walls of pussy blurred as butterflies stirred in Celestia's stomach. She felt a fleshy pair of doors press along her body. Light blinded her a moment later, as did the sight of the two huge pussy lips, which winked at her departure—or maybe just excited at the prospect of devouring her once more.

Princess Celestia then gazed upward, along her naked body—which was drenched with lady cum—and at the fingers dangling at her ankle. She exerted her core muscle to pull herself upward, coming face to face with the nail of said finger and beating upon it with her fists. A moment later, she yelped as the finger pulled her figure higher into the air.

For the tiny princess, she had no choice over her vision. The finger had her facing the body of their owner, raising her up along the toned stomach of midnight blue fur, close enough that some of the strands tickled at her tits.

Celestia thought she'd be clever in looking up, but her jaw went slack in awe at the impressive underside of her sister's boobs. More and more, her own pussy was starting to wink in desire, and she couldn't help but manage a quick rub at her own building desire.

“So you have come to enjoy our game after all,” a voice boomed into the princess's ears. She looked up and right into the grin of her sister's monolithic face, a similar blush burning through the fur of her cheeks. “You wear your mask to maintain dominance in our kingdom. It's just a shame your kink lies in the opposing end of the spectrum.”

Celestia went stiff. The large, teal eyes gazed down at her form like one might an ant. She looked back down out of shame, but when she did, she came face to face with a pink tit. The fingers held her over the massive right orb, before the aerosol of perfect symmetry, and most important of all, the nipple that grew slightly upon being so closely viewed.

“I must say, you've always been more impressive in the chest department,” Luna said with a tone devoid of any jealousy, giggling as her boobs jiggled in response. She felt her little sister shiver in her gasp. “But at this size, the only thing impressive about you is all the places you'll fit.”

Celestia was conflicted: on the hand soaked with her juices, she was terrified; on the hand soaked with her sister's juices, she felt a tingle in her spine that ended just between her legs. The nipple was still before her face, so suckable and slappable, just begging for some hands to rub up and down its length.

The tiny princess began to reach out her hands, but yelped as she was plucked higher into the air. A moment later, she dangled before the massive face of her sister, who titled her head an amused of her prey. Then, the large, plush lips snapped toward Celestia, mouth opening a little wider with every inch past.

Celestia cried at the open maw before her, each tooth pearly white and a tongue slowly slithering out from its resting place. At the back of the dark cavern, the throat opened up in suspense of a new treat—something that made the poor princess's heart stop for a moment.

Then, a gust of warm wind blew over her white body, the touch caressing her sensitive nipples and leaving a tingling sensation downstairs. It lasted for a moment, and in the next, the lips came to a close, and engulfed the tiny in her entirety.

Celestia squirmed at the kiss, the lips softening around her body. It was like being hugged by pillows that deflated around her weight, supplying a constant source of warmth and liveliness. It was dark too, but she had reached a point where she no longer cared.

Celestia was scared, but she was even hornier.

She began to hump against the lips.

Luna could think of no greater turn on than dominating her sister.

Being able to overpower the tiny with her thighs alone? To force a power princess inside her pussy with no chance of escape? To dangle her sister with absolute control on what was to happen next to her? For far too long, she'd been powerless and neglected, and turning the tables rendered Luna at her horniest.

She was just glad the same was true for Celestia.

The tiny princess was struggling against her lips now, caught between them in a kiss, for which, there was no escaping. But something felt different about the tiny's struggles now. Her entire body rocked against her flesh in a steady rhythm—something panic relay allowed.

Luna pressed the tip of her tongue against her lips, tasting not sweat from her sister, but something far sweeter. Then it clicked, and Luna's cheeks went pink.

'So,' Luna thought as she leaned further into the bed framed, sliding her crotch out, 'you've finally fought through the resistance and accepted your guilty pleasure.” She pushed her head out and looked into her generous cleavage. “Time for the real games to begin.”

Luna opened her mouth.

Celestia had been wildly humping against the plushness before gravity took hold of her.

One moment, eyes closed in pure bliss. The next, falling from the warmth back into the crisp air, hurdling to the ground that was vistas below. She screamed, but the rising winds droned her out. Even with the softness of the mattress, the distance was too high to break her fall, but it sure as hell would break her neck.

Was Luna really going to let her die here? Was this some revenge hatched long ago? Celestia's mind ran with as many possibilities as her panic would allow, but they were all silenced once actually looked at what loomed below.

Her sister's chest.

“Luna wait—“ Anything more was cut off by the impact. Celestia's body crashed straight into the cleavage, the boobs shooting upward from the sudden contact, jiggling afterward before settling around their newest guest.

“It would appear you survived the fall rather nicely,” the voice boomed from above, and when Celestia gazed up, she saw her sister looking down at her with amusement. Her arms were clutched at her sides, held in place by the gigantic boobs. “I wonder, if my boobs were soft enough to break your fall, if I should keep you there at all times for your own safety?”

Celestia blinked at that. Something dripped between her legs.

“Tell me, dear sister, does that proclamation interest you at all?” Luna brought her hands to her chest, holding them mere inches from her tits. The sight was otherworldly from Celestia's perspective. “To hide away between my massive orbs, unable to move as I go about my day, commended to go wherever I please and endure whatever I may inflict upon you.”

The hands then pressed against the tits, kneading them with the slender fingers as boob-fat filled out between them. Celestia struggled against her confines, fighting harder the further the fingers came up.

“You could be my most loyal servant, and no one would know.” Luna moaned at her ministrations, throwing her head back. “You could help me pick out my bra every morning, since that would be your home for the day. You will be stuffed underneath my shirt or armor, pressed at all times by my bust, no choice but to endure my every whim.”

As Luna moved up her own chest, she kneaded her boobs hard enough to separate them by a few inches, more than enough for the captive to wiggle out from the cleavage. On her freedom, the tiny princess was more dismayed than overjoyed—the mountainous boobs pressed ever wonderfully on her own bust, and her thighs were wet for a reason.

“But, if I possess a princess to tend to me upstairs...” Luna's hands stopped kneading her flesh, retreating ever slowly to the suspense to the girl standing upon the boobs, before they lowered and disappeared out of her sight. “...then it's up for me to care for downstairs, wouldn't you agree, dear sister of mine?”

The words rang in the smaller princess's mind before they clicked.

“She can't mean...” Celestia gave up the question as she already knew the answer, stumbling forward as the giant she stood upon arched forward in bliss. She fell face first into boob flesh, the midnight blue fur filling around her face as she sunk into the orb—fuck was this making her situation all the more worse.

“You better hurry, dear sister.” Luna leaned back against the frame, eyes still closed as her hips gravitated below. “If you don't act upon your desires, then I'm afraid you'll acquire nothing from this little exchange.”

Celestia slowly rose back to her feet, balance unsteady as her feet sunk into the surface of the boobs. She was hornier than she'd ever been before, and her pussy lips ached for release—to not just hump against softness but to be filled. She needed to be rutted, something to fuck at this size.

The giant began to convulse more and more, keeping steady enough as to not knock off its tiny passenger, but every jiggle of the breasts answered the miniature dilemma. Celestia had slowly been waking forward, along the boobs to their end—nipples long but small enough to fill her entrance.

'I'll have to hang off her boob to do this,' Celestia thought while biting at her lip, standing at the end of the right boob. She looked down at the tit, which leaped up at every jiggle of the flesh. 'Oh to hell with caring! If this is the game we're playing, sister, then I shall steal a piece from you.'

Celestia turned around, looking up the chest, past the mighty throat, then at the face of her giant sister. Her eyes were close and lip bit in pleasure, body rocking with every thrust that she came to moan at. Not know while, she blew her a kiss, then lowered herself to all fours.

The tiny princess yelped in joy at feeling her tits press against the soft boob, the same of which filling along her crotch. She gravitated her body forward and back, rubbing her front along the fat and indulging in the sensation, the fur on fur burning at her skin in the most pleasant of manners.

Then, she began to slide down along the curve of the boob, grabbing a tuft of fur with each of her hands as she lowered herself. In a second, she was dangling off the orb, swaying in tandem to every jiggle of the flesh.

Any fear of the situation was overridden when she felt her pussy come into contact with the nipple, its tip separating her lips and pushing into her tunnel. Celestia threw back her head and moaned the further the nipple penetrated her depths—she wasn't the only one to do so.

“Oh...mhmm..taking matters in your own hands now, huh?” Luna peeked open an eye to the efforts of her sister, giggling at the sigh of her sister dangling over her boob, fucking herself with something as small as her tits. The tiny struggled to rock her hips, not enough strength in her muscles to support such movements. “Seems like they're not good enough for your desires. Please, allow me to supply mine.”

Celestia was too far gone to even glance over her shoulder over the looming shadow. Before she could know what was coming, she felt it, the palm of the giant hand pressing against her back, pinkie slipping underneath her butt to hold her weight. She was quick to understand what was happening, letting go of the tufts of fur and trusting the hand entirely, opening our her arms and hugging as much of the boob as possible.

“A little sister, just a plaything in my hand.” Luna's voice thundered outside the clasp of the hand, but the woman she was talking to just fucked her tits harder. It gave her more cause to rub faster down below. “Trapped between my palm and my boob, she couldn't hope to fight back even if I did this!”

Luna began to knead the flesh of her tit with her sister trapped in the same hand. She heard muffled cries as the boobs filled out along her passenger, and most importantly, almost shooting the entire length of her nipple into the tiny pussy. She groped herself harder and harder, focusing on the sensation on the one caught between it all.

This was it. Luna could feel herself leaking onto the bed, ready to finish. One hand was inside her pussy, rubbing along the wall with a vigor granted only to alicorns. In the other hand, she held her sister against her boob, jerking her into and out of her nipple, delighting in both the sensation and the control.

Before release could come to Luna, it came to an other.

The Princess of the Night stopped her efforts immediately as her tit became wet with something other than sweat. She pulled her hand back, slowly sliding the tiny princess off her teat and up to her eyes, examine how liquid poured down the alabaster legs and how their owner rolled out their tongue.

“You dare cum before it's commanded of you!” Nightmare said, more so shouted into the ears of her charge. The tiny princess snapped out from her euphoria, covering her ears and looking up at the massive face hovering before her. “You were permitted only to finish while inside me, and then you break our sacred contract?!”

“O-Our deal has not yet been broken!” Celestia called back in concern, worried she'd either offended or hurt her sister, both of which she feared for different reasons. “Just...give me a few seconds to catch my breath. I'll be able to go again inside of you.”

“I have no fear of that whatsoever!” Nightmare bellowed once more, sitting up on the bed. A grin cut across her left cheek. “And I know exactly where you shall be catching that breath. If you wish to make up for this wound against me, you'll find your way to my pussy from there.”

“I'm far too small to reach you again!” Celestia cried back, but it did not matter, for the hand that held her lowered behind her sister's back. She had no clue what was happening as the world and the blue fur blurred around her, stomach feeling hollow as she was lowered at increasing speed. “Sister, just what is it you mean to do with me?”

And then she looked down, and then she had her answer.

The royal sisters were beautiful ladies indeed. Each had a bust to kill for, but it was in universal agreement that the solar princess had the bigger bust, and if looks alone were enough to go off, the flesh was mostly likely firmer. Butt, in both senses of the word, all also agreed that the rump of the night princess beat that of her sister.

Which was why Celestia wanted to scream at her current destination.

“C-Can't we discuses this!” Celestia yelled up to the back of her head of her sister, who did not look back at the little cries. The tiny gulped, glancing down at the two giant butt cheeks that filled out below. “We agreed that we wouldn't be doing butts during our first time. I d-don't want to go anyway near your ass!”

“Isn't that just tough for you!” Nightmare replied as he held her prisoner just a few inches above her flank, looking down over her shoulder. Once her sister was looking up at her, she closed an eye and stuck out a tongue. “My ass is going to eat you alive, trap you between my big, round cheek, and with any luck, you'll be sucked closer toward my asshole. Don't worry—it's all clean.”

“That's not what I have an issu—“ The slender blue fingers slid off her body, dropping it into the open air as she plummeted below. She knew better this time then to fear for her life, but in seeing the massive butt that loomed below, she considered having her neck snapped instead.

Nightmare giggled as she felt her butt cheeks jiggle upward from the impact, delighting in the sensation of having a wiggly-jiggly sister in her ass crack. She bit her lips at the power-play, rolling her hips and forcing her tiny passenger along for the ride, feeling minuscule fists beat at her fat.

This would make things up for her indeed.

“Nightmare, this isn't funny!' Celestia yelled up at her sister's back, beating her hands into the cheek as hard as she could, hating herself a little more each time they sunk into the flesh. As was the with her sister's cleavage, her entire body was held tight by the cheeks, slowly swilling her inward with every jiggle. “You can't do this!”

“Oh? But I can!” Nightmare replied, bringing her hands to either cheek, then, with a grin, pulling them apart and letting their prisoner fall. “And I will!” And just like that, she released them, letting them smack against each other and catching something in their middle.

For Celestia, she yelped as she suddenly fell, seeing the cheeks part when she descended further into the chasm. The walls of fat then slapped back into her body, pressing against her tits and even her ass, trapping her at the center of her sister's rump.

“Now isn't this just a treat!” Night's voice came out from her surrounding, but the voice rippled through the fat. Celestia struggled, pushing her feet against the opposite cheek to create some space, giving her leeway to move around. “You fit in my ass crack as you did in my cleavage, and not only that, but it would be easier to hide you in my behind.”

The tiny princess began to crawl downward, her entire body supported by the cheeks. Now that she was no longer in danger, the vast plain of moon butt was starting to grow on her, smothering her just the right balance of muscle and fat. The fur was like that of the giant chest, but the globes here were much softer, and felt much better against her crotch as she crawled.

“Can you just picture it, sleeping every night in my wonderful ass crack?” Nightmare began to rise and fall slowly, the momentum making the globes that were her cheeks move. “I could wake up and forget you were even down there. Walking around with an itty-bitty sister trapped in my ass, forced further up when I put on my panties, denying you the light you enjoy once the pants came on.”

It'd only been a few minutes since she'd last came, but Celestia could feel her pussy becoming wet again. She continued down the ass, moving inwards to the crack, where the cheeks hugged her the tightest.

“Forced to endure every clap of my ass, confirming to every stride that I make.” Nightmare Moon began bouncing up and down on the mattress, all just to feel her ass clap by themselves—a perk of being big downstairs. She moaned every time she halted her sister's progress. “I'd sit down and you'd be forced to take my whole weight, to have my whole ass sitting down on you. You would be utterly trapped, and none of your loyal subjects would be the wiser.”

Celestia gave up in her efforts, and it wasn't for lack of hope. Had she know her sister was this good at talking down to her, she would have agreed to this crazy ideal sooner. Right now, she let her body be savaged by the globes of ass that slapped right into her tits and held her tightly in place. No matter what she said or did, she was trapped in her gigantic sister's rump, who was doing all that she could to dominate her with her bubble cheeks.

“You're...mhmm...enjoying this now....aren't you?” Nightmare stopped bouncing for the moment, and when she felt the wild humps of her sister, knew she had back in the ideal state. She fished a pair of fingers into her crack, separating the flesh until she pinched the tiny at her waist. “You made me wait so long for you to get ready again, it's only fair that you should help me do the same.”

Celestia cried when the fingers grabbed her out of nowhere, dragging her along the walls of ass fat, sometimes sinking as far as she could into it to the ringing moans up above. Then, they let her drop into the palm, which flew forward to grab as much as the ass as possible.

“Oh yes, this is driving me wild indeed.” Nightmare rocked her hips forward and backward, every inch of her cheek filling into the palm and utterly covering the tiny. Satisfied that she had her fill, she took the tiny with her fingers once more, thrust her deep into her crack, and held her but mere inches from her asshole. “Get used to the sight of this, dear sister, for if you break my deal once more, this is where you'll end up.”

Nightmare retracted her fingers, then clenched her ass for good measures. “Then again, I'm not so sure my ass is exactly punishmentfor you anymore.”

Celestia blinked as her sister's pucker was right before her. It was a darker shade of blue, clenched but did not smell, flaring slightly at proximity to a source of warmth. This should have made the princess grimace, being right next to her sister's asshole—so tiny and utterly helpless as to be next to a furry asshole, and yet, her hands rose and caressed the other opening to the massive body.

“Someone is certainly opening up to new avenues,” Nightmare said down at her ass, putting more weight upon it as she sat back. She moaned, letting her head rest back. “I can't see you at all, but I can feel you back there! The deal is to finish inside me, but what way you go about it is up to you.”

Celestia heard the offer as the walls got tighter. The asshole before her looked appealing, and the knowledge of the ass cheeks she would be coming back to made the option all the more likable. But, as much as she would love to explore back there, she had some unfinished objections to the front door.

She began once again crewing down the crack, being hugged on all sides by ass, becoming tighter and tighter until it was no longer tight, and she fell into the mattress face first. She laid forward for a bit, the only moment of respite she had since this all began. It took a few moments to look up, up into the underside of the giant sitting above her.

“She... has no clue I'm under her,” Celestia said in awe as she began to stand up, exactly beneath the center of her sister. “If she moves even an inch, I would be utterly crushed here.” She reached up a hand, rubbing along the area between her sister's ass and pussy. “Then again, while I do plan on being crushed, it certainly won't be here.”

“I see!” Nightmare's voice rumbled from somewhere above, but the tiny sister had stopped caring about such details as she followed under her sister's curves. “My ass is a playing field for another day, but I'm glad you made its acquaintance. Though, you haven't forgotten about our deal, have you?”

“Not at all, dear sister,” Celestia said to herself once she came out from under her sister's rear, turning around to feast upon the gigantic crotch in all its glory. A feminine musk filled the air, the sheets squelching with every step, and the source of all this could be found above. “Your size allows you dominance over my pitiful forum. But you'll see, sis, on why I'm the older sister.”

Celestia took a step forward, gazing at the giant, blue pussy looming before her. The pubic hair was trimmed neatly at the top, the mounds as soft as they looked, and the lips themselves already parted from the previous adventure. Nightmare may not have known she was there yet, but her pussy certainty did.

“Ready or not, Nightmare Moon.” Celestia grabbed each of the mounds to pull herself up, hearing a gasp from above. A moment later, fingers appeared behind her, but they knew better to interfere. She then grabbed a lip with each hand, and pushed them apart. “I'm coming in!”

Up above, Nightmare Moon was conflicted. Controlling her sister with her ass was one thing, but having the tiny slowly climb into her pussy was another. She wanted nothing more than just to grab her and shove her in herself, but there was something so fucking horny about having someone crawl inside her of their own violation.

Nightmare released a moan louder than the rest as her sister crawled her tunnel instead, feeling her nether lips seal themselves behind her. Every inch her sister crawled inside her was another injection of euphoria. She brought her fingers against her vagina, pinching the lips closed so there was no escape, and rubbing a finger up and down her vulva.

Inside Nightmare's pussy was paradise.

Celestia felt strong when she had pulled apart her sister's lips, crawled into the pussy a hundred times bigger than her own, and let the convulsions carry her deeper inside. She surrendered completely to passion as one hand kneaded her tit and the other her ass.

“You're...oh my god...you're inside of me!” Nightmare's voice rumbled all around the tiny princess. “I have total control over my sister with my pussy alone. My pussy!” The walls then suddenly clenched around her, some of the juices washing into Celestia's mouth. “How does it feel, princess of the sun, to be totally trapped by my pussy? To know that there is no escape unless I finish, in which you'll have the life sucked out from you by my walls.”

“It feels wonderful!” Celestia cried out in joy, humping against the walls as they undulated against her. “I'm inside your pussy without any hope of escape! My tiny, little sister can control and do whatever she likes with me. She could put panties on and go about her day, and none would be the wiser!”

“My my, sis!' Nightmare replied. Her body began to shift as the tiny prisoner was flung across the walls, feeling herself slide down the wet walls. When she looked over to the pussy lips, a small light shone into her prison, letting her see the flat hand held before it. “You've given me quite the idea, and I hope you're ready for a ride! Now's the time to pay up!”

Celestia watched as her prison slammed forward into the palm, then again, and again, feeling the body she as trapped inside lurched every time it humped the hand. She was flung around inside, a different direction with every hump, enjoying every time her ass and chest was clenched with the walls.

This continued for a few moments, before Nightmare felt herself beginning to close. Taking the hand she humped, she interested her fingers past the lips of her pussy, reaching in and grabbing her tiny sister, rubbing her up and down the length of her tunnel.

“I have total control over you sister! You are mine for as long as I desire!” Nightmare rubbed her inner walls while pinching her little sister, caring not for any damage done as she went faster and faster, tossing her sister in as far as her pussy would allow, then pinching her lower lips shut and crossing her legs tightly. “I'm about to cum with my sister trapped inside of me!”

Inside the pussy, everything was a blur for Celestia. She'd been grabbed by the waist and rubbed along the walls at a pace she could never hope to comprehend, only the traction against her own tits and pussy was good enough for her to come then and there, before being discarded near the back of the tunnel. She tired to stand, only for the cave to close in on herself, the muscles clenching their tightest as cum flowed outward.

Celestia was too tired to move, too sore to fight against the white currents as they carried her toward the entrance. She was slightly confused as the interior remained just as dark, and the waters began rising up.

“That. Was. The greatest release. Ever.” Nightmare's voice came in pants around her, the pussy lips just as tightly pinched. “Tell me, how does it feel to be trapped with my juices, to be so close to freedom but held back by mere fingers?”

Celestia could not muster a reply.

“Hmm, I suppose our game has ceased.” The pussy lips opened to blinding light, and a moment later, the tiny princess felt herself fall into the soaked mattress below. She looked up, up into the distant face of her pleased sister. “You did well to give in to your desires, as well as to please me in a way these fingers could never mange before.”

Those same fingers picked up the limp princess, bringing them before the face of the giant.

“Hate to have to tell you this Tia, but it'll take many baths to remove my scent from you.” Nightmare had sniffed her sister a few times before speaking, coming to smile when the other did the same. “You know, day is just beginning for the rest of your kingdom. Do you think you're in any state to rule?”

“I...I have to,” Celestia groaned, trying rise in her sister's grip, but failing to do so. “For a thousand years, I've had to be princess weather I wanted to be or not. My subjects wouldn't take my absences for the excuse of misery, so I very much doubt they'll do so for pleasure.”

Nightmare bit her bottom lip. “What if... I stepped in for you?”

Celestia blinked at that. “You would be willing to pull a double shift?”

“You were forced to do so for me,” Nightmare said, then coming to grin. “But, if this little session has made you comfortable in the art of being tiny, perhaps you could pay me back for taking your place?”

“And just would that be?”

Nightmare looked down at herself, making Celestia do the same.

“I see,” Celestia said in a tone of hesitation, before sighing the whole thing away. “Okay, that's fair. You take over my duties, and you can have tiny ol' me for the whole day.”

“The whole day!”

Celestia nodded.

“Thank you big sis!” Nightmare reverted into Luna, then bringing her sister in for a big kiss. “You won't regret it! I'll manage your affairs just the same, and we'll both feel just as good about what's to come next, alright?”

Celestia did not need to reply. If she was honest with herself, she was going to come to enjoy the following arrangements quietly nicely. Paperwork was always a bitch, but it's more manageable when you're tucked in the cleavage of your attractive sister, and she's doing all the work.

But when Celestia was lower past her sister's bust, she started to become worried. “Uh, sis? Are you putting me in your ass instead?”

“No!” Luna replied in glee, and a moment later, Celestia was facing her pussy lips again. “You said I could have you, so you get to spend the whole day inside my pussy! I won't have to worry about you falling or getting lost, and I'll be able to feel you at all times!”

A moment later, the fingers pushed her face against the slick lips, pressing her slowly into the folds. “I may forget about you at times, though, but I'm sure my walls will make for plenty of fun for you down there!”

“Luna, I'm not sure—“ And, just like that, the fingers shoved her deep inside, as deep as they could go, and left her in there. The slender two fingers slid out from the lips, giving her pussy a pat as it almost burped from it's latest treat, before flying up to their owner's eyes.

“Sis has sure spent a lot of time between you two,” Luna said to herself, putting her fingers into her mouth, tasting both herself and her tiny sister. The lingering juice made her well some more downstairs, but that could be delt to the confused movements she felt inside of herself. “She may get some bad ideas if I don't do something.”

Luna stretched her arms upward and cracked all the kinks in her neck and back, yawning at the day that was to come before it. She then looked between her legs, at the small puddle that stained her sheets, as well at her own pussy, which seemed small to her eyes, but massive to the one trapped in their depth. She gave them a little pat, something strong enough to make the passenger inside fall on her ass.

“Feels kinda weird to know I have sis inside my pussy, that I'll be going about my day with her in there.” Luna turned around and put her feet to the ground, standing up from her bed and giving one last stretch. She then walked over to her dresser, sliding out a drawl and picking out a pair of black panties. “These are sis's favorite pair, but seeing as how we're of the same vagina, she shouldn't mind if I borrow them.”

Luna bent over and put her feet into the panties, sliding them up her legs until they became snug around her pussy and ass. Celestia always had a bit of a smaller butt than herself, so it made sense why the panties would be tight. She walked over to the standing mirror.

“These may be a bit uncomfortable,” Luna muttered to herself as she began striking poses, feeling her little passenger tumble about the inside of her. At one point, she slammed against her pussy lips, but has no chance escaping past the panties. “But they also make sure that lil sis can't escape at all, even if it's just to sit back in the panties.” She turned around and admired her ass. “Not only that, but my butt looks bigger and comes out more.”

She then clasped her hands behind her back. “These will be perfect for today!”

And so, that's out this particular story ends. Luna would go on to pick out an outfit and run the day's court, enjoying the sensation of the passenger inside her pussy. To her credit, Celestia did not hate this as much as she thought she would, and excitement of her sister moving, about the outside world while she was trapped in here—it made her ready for round three.

'My sister may have been clever in keeping me in here,' Celestia thought, standing up in the tight passage, 'but there are still ways for me to take my revenge.”

She giggled.

'Hope you don't like to embarrass yourself, Lulu.”