After a freak accident shrinks Celestia, Luna unkowingly sits on her and traps her in a trial both foul and dangerous. Will Celestia surive the ordeal, or will her story end within the depths of her younger sister?
Warning: This story contains Microphelia content, Anal Vore, Scat, and some pretty disgusting scenes. It is not for the casual reader looking for their next fic. If you aren't a fan of those fetishes, I highly recommend you find something else to read. This story is not for you.
A thousand years is a long time for a pony to live, and in such a long life there are bound to be some strange and unusual tales. Some public knowledge, some private; this story is the latter. While lowering the sun, a magical anomaly causes Princess Celestia to shrink, marking the start of a horrifying ordeal brought about by Princess Luna doing something as simple as siting down.
There are many strange events that have taken place in Equestria over the centuries; a mismatched monster capable of bending reality to his whim taking over as tyrant, a small army of identical ponies stampeding from the Everfree, a kingdom that fell to ruin because the two rulers were poisoned to love each other, and many other things that can--and have--filled many tomes. But perhaps the strangest story of all is one you won't find in any book or letter, but in the most secret of memories held only by the two Princesses of Equestria; Luna, and Celestia.
That night, cliche as it may sound, started out as any other. With the last petitioner gone from the Day Court, Princess Celestia allowed herself a moment's reprise before finishing the last task on her agenda; lowering the sun. Once upon a time, this part of the day was her least favorite; every night, for a thousand years, Celestia would lower the sun and raise the moon. And every night, she would remember the scream tearing from her sister's throat as she was banished to her prison, and the cold emptiness that formed in her chest.
This reprise used to be a time to steel herself for her task, a way to prepare for the flood of emotions that would overwhelm her otherwise. But now? Well, now it was a moment of peace; as Celestia looked out from her throne, her horn lit with magic powerful enough to move planets, she guided the sun along its final tract over Equestria's horizons so that it may share its warmth with those beyond.
As Celestia began to lower the sun, it was Luna's duty to raise the moon. The mare in question was currently on her way to the throne room to fetch her sister for breakfast--or dinner, in Celestia's case--before beginning her own royal duties. It was while walking through the hall leading to the large double doors of the throne room that she saw the vibrant light of the sun's rays start to fade from the sky.
Luna allowed herself to smile at this as a soft glow enveloped her horn; like a mother stirring their foal from slumber, the Lunar Princess gently coaxed the moon from its place at the edge of the land and raised it proudly into the night, starlit sky. The bright colors brought about by the day were replaced by the the subtle, muted tones that were only visible under moonlight. In the thousand years she had been banished, Luna had felt nothing but resentment for what happened to her.
But now, purified of her evils and with a mind free of jealously, she felt nothing but joy at seeing her moon take its place among the small, twinkling stars that dotted the sky. She missed this almost as much as she missed Celestia... even if she was too blind to realize it before. The Diarchs of Equestria both watched the transition of night and day through the windows; one from her throne, the other from the hallway.
What happened next was something neither Princesses would be able to explain; perhaps their magic was cast out the same time as a fluctuation, or maybe one of them accidentally interfered with the others spell. The reasons didn't matter, but the results? That was where this story truly starts.
Both Princesses felt it; a swell of magic, a jolt that shot through their bodies. For Luna, it resulted in little more than an unpleasant tingle--like she had somehow pinched all the nerves in her body and made herself numb--and a rather disorienting headache. But for Celestia? The results were much more... physical.
She was numb, and there was a dull throb at the base of her horn, but even more worrying was how much bigger everything was. The cushion to her throne was large enough to seat Ponyville, if only just. The carpet leading to the throne room door looked like an ocean of red stretching endlessly into the horzion--she barely make out the outline of the door, it was so far away.
It was understandable, then, that the first thought that came to mind was this:
"Discord, if this is a joke its in terrible taste."
And that was most definitely a thought, because even though her muzzle moved to sound the words, no noise escaped her lips. She tried again, and again, but no matter how many times she opened her mouth nothing besides the rush of air escaping her lungs came out.
Next, she tried to cast a spell--to see what happened to her. That too failed, only producing a few sparks for her effort. Whatever it was that made her this small, it burned out her vast stores of magic in the process--even her hair, normally flowing in a cascade of rainbow colors, had faded to its original pink color. She was till trying to work her mind around what happened, when she saw the doors to the throne swing open, and a blurry blue form walking towards her.
Luna did not feel good. As her magic pushed open the great wooden doors to the throne room, the throbbing at the base of her skull only grew worse--had she not cut off her magic so suddenly, she had no doubt even something as simple as opening a door would prove difficult.
"Tia..." Luna's eyes were clenched shut, her hoof rubbing the base of her horn in hopes to work the pain out. Unfortunately, the act seemed to be making the appendage hurt worse, as each time she touched it her face contorted in what could only be described as minor pain. "We--I think something happened whilst raising the moon. It feels as though our horn is about to burst... Did you happen to feel anything when you..."
As Luna's eyes opened to a blurry, tear filled sight, the rest of her words died in her throat upon noticing the very apparent lack of her sister's form sitting on the throne.
"Did she already go without me?" Another jolt of pain shot through Luna's horn, and with a grunt of annoyance she walked along the red carpet leading to the throne with heavy hooves before planting her royal rump unceremoniously upon its plush cushion. For a moment she had felt an itch beneath her tail, but with much more important things on her mind that what might be causing it, Luna simply grinded her rear into the seat until the minor annoyance vanished.
Much to her frustration, all the clenching and squirming she did only seemed to make the itch feel deeper. It was actually starting to become embarrassing; she was rubbing her butt on the throne like a common dog. With flushed cheeks Luna rose from her seat and lifted her tail; since nopony was around, she might as well drop all subtly and deal with the problem directly...
Once Celestia was able to make out the approaching figure was her sister, she felt a swell of relief flood through her. Between her and Luna, it wouldn't be too hard to get in contact with Discord and make him fix this. Strangely enough, a part of her wondered if it really was Discord's fault that this happened; magical anomalies were not uncommon in Equestria, but for something as extreme as this... it seemed too much like a prank to just be a coincidence.
Her musings, however, ended as soon as the massive form of Luna dwarfed her vision. It was quite a marvelous sight, really, to see her sister tower over her like a mountain. At her size It almost looked like her mane could actually be the night sky. Celestia waved to her younger sister, only for confusion, then fear to replace the wonder.
Luna was turning around. For some reason she couldn't see Celestia, and as the view of Luna's forelegs, barrel, head, and mane were replaced by her hindlegs, flank, and tail, it was all to apparent to Celestia what was about to happen. With a great flap of her wings, the Alicorn launched herself into the air in hopes that she could escape the impact zone before it was too late--what she didn't count on was how fatigued her body would feel. The take of was slow, lethargic, and it brought her to the point of near exhaustion just to get off the seat.
She was smashed into the cushion of her own throne as Luna's rear slammed into her like a meteor. Now, while being trapped beneath Luna's flanks wasn't even last on the list of things Celestia ever wanted to do, if that was all that happened than maybe Celestia wouldn't be as horrified as she was now.
She was not trapped beneath Luna's flanks, but between them. She could feel the hot ring of muscle that made up the Lunar Princess's plot pressed against her back, and with each breath her lungs were filled with a mix of the spicy, pleasing scent of lilies, roses, and jasmine mixed with a hint of cinnamon, clove, and anise combined with the pungent, earthy fumes pouring from the musky orifice above her.
It may surprise some to hear that Celestia, while both afraid and embarrassed to find herself under her sister's posterior, did not truly mind the smell. It would be a lie to say she liked it, and it would be even more wrong to say that she wasn't disgusted at the thought of breathing it in, but Luna was at least very thorough while bathing herself and her soap--which was meant to smell like moonflowers--was at least strong enough to at least diminish the natural scent of her tailhole.
Still, that was hardly a comfort to the Sun Princess as she tried to squirm her way free--and act which, unfortunately but not surprisingly, only managed to make things worse. With a startled gasp of breath Celestia's body was pressed further into Luna's hole as the massive ponut smashed, rolled, and crushed her body against its twitching flesh and even--to her horror--partway inside it.
She wanted to struggle, wanted to fight hoof and horn to escape the heated prison in which she found herself gripped by, but even her body was wedged partway within Luna's hind-quarters, and the air lost its floral scent to the more fetid smells of Luna's depths, Celestia knew that trying to escape further would only end in greater misfortune.
As an Alicorn, Celestia could afford to be more patient than a normal pony would in this situation. She remained still as she could, even as the muscle continued to clench and push against her in some vain attempt to stifle the irritation she caused. Even as the oxygen in her lungs were squeezed out, and faint traces of methane began to take its place within her, this wasn't anything she couldn't handle physically.
Mentally, though... Celestia wasn't sure if she'd ever be able to look at Luna the same way after this.
After a few seconds of being treated like an anal chew toy, Celestia's patience payed off she felt her the G-Forces of Luna standing up slam into her body. Greedily, the tiny pony sucked in the fresh air as soon as she was able; given where she was and how deep she was pushed inside Luna, it was only natural that the air still bored the scent of the Alicorn's hind-quarters, but the scent was bearable so long as the air wasn't produced in Luna's colon.
Celestia's struggles to escape resumed immediately; she was sluggish, yes, but even though her voice was gone and her magic was currently sapped, her wings could still hold her aloft if she could just use them. Perhaps if the circumstances weren't so dire, the Solar Princess would have noticed how mesmerizing the sight before her was--strange thing to say, I know, but just try to picture it; just ahead of Celestia, constantly rippling and flowing through the air as if caught in the breeze , was a perfect image of an entire galaxy born within Luna's tail.
Where Celestia's mane and tail were an aurora of light and color, Luna's was a nebula; stars both dim and bright twinkled in the ethereal mass of blues and purples--moreover, whenever the light managed to strike her hair just right, the colors would change or darken, allowing yellows and black into the spectrum while simultaneously accentuating the natural, ever present hues.
Strands of faint, wispy blue hair writhed and swayed in translucent beauty, occasionally giving the impression of shooting stars being vanishing back into her mane or tail. As hard as one might try, to convey the beauty of Luna's mane and tail they would have to describe the beauty of the night sky itself--something I fear is beyond my own meager abilities.
Celestia had almost freed herself from her unwitting captive, and perhaps as she flew away she may have been able to marvel at the beauty her sister held, but instead of freedom a blue light matching the color and feel of Luna's magic enveloped her and the sphincter, and instead of flying out she felt her body being shoved deeper in, the feeling that somepony was scratching her entire body following her as she was forced deeper and deeper.
No more was the air safe the breath, nor did she smell the scent of moonflowers mingling with the musk--instead, with each panicked breath Celestia took, her nostrils and lungs were assaulted with the putrid scent of pony waste. She began to feel a slimy substance she really didn't want to think of cling to her pristine white fur, as the heat radiating from Luna's insides rolled over her as if she stepped into a sauna.
The pushing stopped before Celestia breached the other side of her sister's sphincter, even as the magic continued for a few seconds longer. Just as quickly as it happened, the spell ended, and with a silent scream that could only be heard in her own mind, Celestia was enveloped by the filthy walls of Luna's inner ponut and held firmly in place as the mare outside resumed her night...
A pleased moan escaped Luna's muzzle as her magic pressed deeper and deeper into her rear, scratching the entirety of the plothole until the itch completely vanished. The mare clenched the muscle a few times just be be certain, but once she was satisfied the irritation was dealt with Luna took her leave of the throne room, only stopping outside the door to address the guards.
"By any chance did you see my sister come by?" She asked curiously.
After being informed that no, Celestia had not left the throne room, a mischievous smile began to spread across her lips. She thanked the Guards and began making her way towards the dining room--where her so-far absent sister no doubt waited for her.
"Getting cocky, aren't we Tia?" An amused whicker escaped the Lunar Princess as her smile morphed into a grin. As soon as she opened the door, something was going to happen--Celestia thought Luna would be easy to prank, so much so that she made it blatantly obvious it was going to happen.
Now, this may seem like a leap in logic to some, but this wouldn't be the first time Celestia had done something like this. A few weeks after Luna was purified by the Elements of Harmony, Celestia informer her that she was going to be pranked during her shower. Believing her sister's prank was to make her shower wrought with paranoia, Luna walked out of the bathroom with a brand new pink coat.
A few days ago, Celestia gave Tiberius--or Tibbles, as Luna affectionately called the little possum--a letter that told her that she wasn't feeling well, and wouldn't be coming to breakfast after raising the sun. When Luna woke up, she had a mustache and manacle doodled on her face with a post-it note stuck to her mirror that said "feeling much better now =)".
And that was only two examples. Needless to say, Luna wasn't going to risk actually opening the door lest something fall on her head. Instead, the mare gathered her magic into her still throbbing form and, with a burst of light, reappeared on the other side.
"Hah! I will not be fooled this time Tia! You--oh, she's not here..." Not yet satisfied that she was safe, Luna cast a quick spell across the room to make sure her sister wasn't hiding somewhere. Oddly enough, she got an incredibly faint trace of the older mare somewhere... behind her? Odd... just to be sure, Luna's tail swatted at the air behind her rump--just in case Celestia cast an invisibility spell--only for it to strike air instead of pony.
"Did she do something to my magic?" She muttered, cautiously making her way over to the table while trying to figure out what Celestia's plan was. If she was responsible for the influx of magic, than that would be a very low blow indeed. Still, after reaching the table without any incident, Luna sat down on her cushion and--
immediately deadpanned as the seat began to sink with a long, drawn out farting sound ripping from beneath her.
The prank shortcut, and one of the oldest, simplest tricks in the book; Celestia replaced Luna's seat with a whoopee-cushion, and to add insult to injury the mare wasn't even there to enjoy it.
"Very well, Sister. If that's how you want to play this out..."
Luna knew exactly how to get back at her sister; it wasn't the most ingenious plan, but than neither was a whoopee-cushion. After blowing the false cushion back up, Luna swapped it with Celestia's seat and, with a mischievous smirk and a quick, mild-pain inducing invisibility spell, Luna snuck into the palace kitchen with the sole intent to find the cake that was inevitably going to be served as Celestia's desert.
The smirk only grew once she found it. With small pop, a tube of toothpaste appeared next to the Alicorn and with glee more suitable for a foal than a princess, she began to decorate the baked good with her minty vengeance. Once done, she returned to her seat and began eating her breakfast, patiently waiting for her sister to arrive.
After ten minutes, Luna's patience was beginning to wear thin. Five more, and impatience began to give way to worry. Where was she? Being late was one thing, but not showing up at all? That wasn't like Tia.
And just like that, ten minutes became twenty, and Luna's worry drove her to begin searching the castle for her wayward sister. Much to her annoyance, the itch she had earlier felt like it was slowly crawling back up from her depths--she was too concerned for her sister to wonder about the source of the itch, and after making sure nopony was around to see it, she once more plunged her magic into her hole; this time making sure to go as deep as possible to--hopefully--keep the itch from returning.
Satisfied that the offending irritation would no longer bother her, Luna walked to one of the Castle Balconies and--with a flap of her wings--launched herself into the nighttime air. Searching the castle would take to long, and after casting a few cantrips to make sure the pain in her horn was truly gone, she began to cast a sensory spell across the Castle as she flew from one part of the grounds to another--if Celestia was still on the castle grounds, Luna would find her.
Celestia Chapter: Somewhere Nopony Was Meant to Go
An Alicorn's body was strong--unbelievably so, in fact. With a stomp the earth itself would fracture and break, with a simple spell both sun and moon moved at their will, and their durability allows them to survive being driven through even a mountain. Knowing that, it might not come as a surprise that various... other parts of their body would carry the same unearthly feats.
Celestia, nestled deep within the fetid ring of Luna's plothole, was learning this all too well. Every part of her body was being subjected to pressure strong enough to crush stone, and with each clench of muscle the mare felt her bones creak and muscles flex--it was only by the strength of her own Alicorn body that Celestia wasn't reduced to a red smear within her sister.
Micrometer by micrometer, Celestia tried to pull herself towards the exit. She was scared--and why wouldn't she be? An event like this has never been recorded in the thousand years she had been ruler, so either this was the first time it had happened, or nopony had ever been found to document its occurrence. She even ruled Discord out as the culprit--even at his most depraved, the Draconequus would never subject somepony to this torture.
It was like being buried alive. The only thing Celestia could feel was the warm, slimy walls of Luna's plot pressing against every part of her body like a vice. It was pitch black, and a disgusting filth Celestia didn't want to think about had made its way into her nose, eyes and mouth--it was suffocating, and the only thing Celestia wanted to do beyond escape was scream.
A wave of magic washed over her body, and it was as though a great big flashbulb had went off in her eyes. A sense of displacement without being anywhere different--even a magical novice would be able to know teleportation by feeling alone. Not that knowing helped Celestia any in the long run--Luna had teleported, but Celestia's position didn't change in the slightest.
She was resolved to continue her climb towards escape, when suddenly she felt her center of gravity shift; she felt her organs drop ever so slightly towards her hooves as though she were taking flight, her bodies mass pull back towards Luna's colon, and with an agonizing clenching of muscles, felt it all stop.
The only sign of where Luna was came from the faint sound of a whoopee-cushion from somewhere below. The dining room... Celestia felt a surge of hope blossom in her chest; if Celestia didn't show up to eat, Luna would eventually start looking for her. All she had to do was escape, find someplace safe to sleep, and Luna would seek her out in her dream and this horrible ordeal would finally be over!
She wasn't able to move with Luna's weight bearing down on her like it was, and if the pain in her barrel was anything to go by her ribs were likely broken, and her wings felt like they were about to snap, but all she had to do was wait...
Much to her surprise, she didn't need to wait long before Luna stood up again. Celestia wasted no time in resuming her escape efforts, and whatever Luna was doing out there she was taking long enough that Celestia was confident she would make it out before her sister sat back down.
She was wrong, but even as the familiar feeling of G-forces slammed into her body, she had managed to get close enough to the end that she could afford to wait a little longer. Celestia never truly appreciated how amazing the body of an Alicorn was; her durability kept her alive under the constant assault of Luna's plot, her strength allowed her to pull herself forward, and even deprived of oxygen for as long as she was she was still able to move, think, and live. If she were a normal pony, she would have died a million horrible deaths in this place.
With that thought, a surge of determination washed over Celestia. She was the Princess of the Sun, the mare who brought her ponies the warmth and light of day, the ruling Princess of over one thousand years! She's survived countless tragedies and battles, and once she survived this one, she would ensure nothing like this ever happened to one of her little ponies... and if she wasn't the first,that it would never happened to another.
And so, Celestia waited... and waited.. and waited, until Luna eventually stood back up.
Unfortunately for Celestia, this wasn't the answered prayer she was hoping for. With each centimeter she crawled, Luna's rectum clenched with more and more pressure--it got to the point that Celestia couldn't even move her legs, let alone continue. Once more Luna was aware of her sister, and in a cruel repeat of history Celestia saw the faintest rays of line before her vision was overcome by the blue aura of her sister's magic.
Her own horn sparked painfully in a futile attempt to ward off the incoming wave of magic. Her ideas, her plans to prevent this from happening to any of her subjects--as she felt the foul flesh of Luna's inner sphincter parting along her sides, the magic burying her deeper and deeper within her sister's rear, the determination she felt melted away into despair.
"L-Luna, stop!"
It was a hoarse sound, Celestia's voice, as though she hadn't used it in years. Unfortunately, even if Celestia's voice was normal for her size, the sound still wouldn't have reached the younger Alicorn's ears. The walls separating Celestia from Luna's colon finally reached their end, and with a gasp of air so noxious it made her stomach lurch and lungs lock up, Celestia found herself falling into the soft, slime coated walls of Luna's intestines, the faint blue light briefly illuminating her slick surroundings before fading and allowing the sphincter to once more close.
The inside of Luna's bowels were like a world all to themselves. Celestia's ears constantly twitched as the chorus of gurgles, groaning, and thumping sounded endlessly from all directions. She felt the blood running through Luna's veins throbbing beneath her back, as bile and excrement stained her shining white coat, all the while trying not to inhale or taste the indescribably putrid miasma that made up the air of Luna's depth's--in all of Celestia's years of living, the only thing she had smelt even remotely as bad as this was the Canterlot sewers, and even that paled to the stench fighting to infect Celestia's lungs like a disease.
As the Alicorn moved to stand, her body and hooves sunk into the cushiony floor with a disgusting squelching sound, the overwhelmingly muggy heat radiating from the giant mare pounding into Celestia all the while, driving her already throbbing pores into overtime. As soon as she managed to rise to her legs however, her body was slammed right back down.
Luna must have started flying--no doubt in hopes of finding Celestia. This proved to be a problem for the tiny mare, as each time she tried to stand, Luna would bank, rise, fall, or dive causing her to lose her balance all over again, and almost every time she fell she felt herself slide further and further into Luna's intestinal tract.
Celestia had believed being crushed by her sister's anus had been the worst fate imaginable, but in here? As Celestia's tongue was forced to endure the taste of manure, and her lungs filled with gasses so putrefying they could kill a fly? There was nothing less true than that.
Minutes passed, maybe hours, before the fumes finally began to reach Celestia's mind. Her horn flickered a few times before finally managing a simple light spell, and her hopes shattered completely at seeing the mound of waste several times larger than she was looming ahead of her.
She cut off the spell, not wanting to see anymore, and finally began to break down. Her ponies, her kingdom... she wouldn't see any of them ever again. Everything she'd accomplished in life and this was how it would end for her. Not of old age, or in battle, but in the most revolting organ in her younger sister's body...
She didn't even fight to remain conscious, allowing the sounds of Luna's body to lull her into an restless unconsciousness.
An hour passed since Luna had began her search for Celestia, and so far she hadn't found a single trace of her diurnal sibling anywhere in Canterlot, even with the help of the Royal Guard. Image upon image flashed through Luna's mind on what could have happened to her sister; Running away? No, she loved the ponies of Equestria too much to drop everything and leave. Hiding in Canterlot? Luna had searched every corner of the city and hadn't found so much as a trace of her sister's magic. Foalnapped?
Luna's eyes widened at the possibility of Celestia being taken. As much as she hated to admit it, there hasn't been a time since Luna returned as Nightmare Moon that Celestia hadn't be incapacitated by whatever villain sought Equestria as their own. Herself, Discord, Chrysalis, The Everfree Forest, Tirek--excluding Sombra, Celestia had always been removed from the picture in some way or another.
With a flare of her horn, Luna teleported into her bedroom, taking a seat on her bed and closing her eyes as the spiral of her horn began to glow white. If Celestia is asleep, Luna should be able to find her in her dreams, and now that the whole of Canterlot is out looking for her on hoof, she was free to search the Dreamscape without worry.
Luna remained like that until it was time to raise the sun, trying desperately to find Celestia within the mass of dreams. She had managed to find Celestia a few times, but the dream never lasted long enough for her to enter it. A pit of anger began to form in her gut, and with each failed attempt her body began to burn more and more in anger until, finally, she cut off the spell and threw a magical tantrum; sheets flew off her bed, lamps flew into the wall, paintings were blasted into dust and books were tossed haphazardly across the room as the Lunar Princess screamed in rage.
After a few minutes, Luna's rump hit the ground with enough force to crack it before looking out her window. With a defeated sigh, the mare's horn glowed as she lowered the moon over the horizon and brought the sun out from its hiding place--the fact that there was no resistance at all only furthered to sink Luna's already horrid mood.
Celestia was really gone. Until Luna or the Guard could find her, Luna would be responsible for running everything... just like Celestia was for the last thousand years. Luna wanted to both sit there forever, and tear Equestria apart rock by rock until she found where Celestia was being hidden.
"Where are you, Celly...?"
As much as Luna wished she could just sit there and will Celestia to return, the gurgling in her gut and pressure in her bladder and rear reminded her that she'd been ignoring the call of nature for the past several hours while looking for her sister, and that if she continued to hold it in she would likely burst.
A sudden jolt shot through Celestia's body, shocking the mare back into consciousness. While it wouldn't be a lie to say Celestia was relieved that she had woken up, the state she found herself in did little to stoke the fires of hope that struggled to burn within her. The first thing she noticed was the unbelievably horrid taste in her mouth, the burning in her eyes and the feeling of <i>something</i> trapped within her nostrils. Her legs, her wings--her entire body was trapped within a warm, firm substance that refused to give no matter how hard she struggled.
Celestia wasn't stupid. She knew where she passed out, knew by the flavor pervading her tongue and stimulating her gag reflex that she was trapped within the reeking refuse of Luna's colon. For a moment, she even believed she was still lost within the winding tunnels of the Alicorn's bowels--that belief was ended as a hot liquid began to seep threw the walls and begin to soak into her coat.
The mare pushed aside the more toxic thoughts that flooded her mind and instead focused on the one good one; she was in the toilet, which meant she still had a chance to escape and find help--that chance would be gone the moment her sister flushed, so she had to act fast. She gathered up all the strength left in her body, and with it she tried to move. She had no way of knowing how deep she was within the mass of waste, but she knew that she couldn't be that deep within it--she struggled, and she struggled, but while her legs were able to push some of the filth away, it was not enough to push through.
For the first time in centuries, Celestia felt true and utter despair. She wasn't strong enough to break free... the thought of Luna unknowingly flushing her down into the Canterlot sewers, where eventually even her Alicorn body would fail her.
That thought, the thought of dying in a sea of refuse, was what gave her the strength she needed to break free. Anger and determination filled her body, and while the sludge she was trapped in kept her from moving, it did nothing to stop her magic--she ignored the pain ripping through her head, focusing solely on gathering up all the magic she could before releasing it in one, powerful burst.
No more! Celestia was the princess of the sun, the ruler who kept Equestria running for the past thousand years, an Alicorn with enough power in her body to move both sun and moon! She would not meet her end in a toilet bowl!
As the spell faded, Celestia soon felt the rushing of water slam into her form. The warm liquids mixed with the thick, clay-like excrement stuck to her fur made for an all around unpleasant feeling as the Alicorn swam, kicking and flapping, towards the surface of the water. She was going to escape; even as the occasional, building sized logs of waste splashed into the yellow-tinted waters and threatened to pull her down as they past, she persisted.
With a gasp of fresh--if not odorous--air, Celestia finally reached the surface. While she wouldn't admit it, the sight of Luna's rear looming above her, blocking out all but the thin rays of light shining in from between her legs, shook the tiny Alicorn's resolve, even if for only a moment.
She had been at the mercy of her unwitting sister's posterior for the entirety of the night. She had been inside of her, had been caked in waste, and squeezed out the opening that, even now, quivered and puckered to allow yet another mound out from the winding tunnels laying behind it.
It was only because of the explosion that erupted from the filth covered sphincter that broke Celestia from her trance. She was so close now, she just needed to go a little farther. Forcing her eyes away from her sister's plot, Celestia gave a mighty flap of her wings and lifted her body from the pond, even as she channeled more and more magic that she didn't have to her voice.
"LUNA!" she cried, flying ever closer and closer to the opening in her hindlegs. She flew past the logs of waste as they fell from the massive mare's body above. She flew high enough to make out the giant abyss of Luna's marehood, and even lost a few inches of air as she was unexpectedly shot by a burst of pee. As she grew closer to the light, she was able to make out the fine hairs--trees, in her current sized--of Luna's coat until finally, finally, she reached the outside of the bowl.
Celestia, having extended all of her patience, looked up the massive blue body of her sister--still flying--and released her magic in one, amplified word.
As Luna's ears twitched, she couldn't deny that her heart may have skipped a beat or two. Her eyes were immediately drawn down towards the noise--towards what sounded like her sister's voice. She felt her cheeks flush at the sight of a small, brown bug flying up from the toilet. Was that what was making her plot itch? Disgust and anger mixed in her mind as she gave the insect a steely glare, her magic unraveling a strip of toilet paper to catch the offending creature in and dispose of it like the filth it was!
But, as she moved to catch the bug mid flight with the tissue, something stopped her. Perhaps it was her own fried nerves, but it sounded like Tia had called for her... but that couldn't be, could it? Curiosity getting the best of her, Luna grasped the bug in her magic and levitated it closer to her face. Her muzzle scrunched as the faint whiff of horse apples tickled her senses, but her eyes widened at what she saw.
With a quick spell to make sure she wasn't just imagining things, Luna's suspicions were confirmed this wasn't just a bug that she accidentally shoved into her colon... it was Celestia.
"Tia...?"
While it would be a lie to say Luna wasn't overjoyed at finding Celestia relatively unharmed, that jubilation was tainted with embarrassment, horror, anger and sadness. The same could easily be said about Celestia; she was alive, and she was happy and relieved to the point of tears, but even as Luna was delicately washing her tiny form free of all the muck and filth it had accrued while inside her body, she couldn't help but feel anxious whenever she looked at--or even thought of--her younger sister.
In the end, Discord was the one who reversed the spell. After ignoring Luna's summoning the night of Celestia's disappearance in favor of swimming in the Milky Way--after turning it into real milk, of course--the Lunar Princess immediately assumed the Draconequus was behind their torment. After both restoring Celestia's size and spending several minutes trying to prove his innocence, Luna finally agreed it was a freak accident--one that both Princesses would look into to ensure it never happened to another pony again.
Luna remained awake to deal with the dealings of the Day Court as Celestia recuperated from her ordeal. It took several weeks before the sisters could really enjoy each others company again, and even to this day the two can never look at each other without remembering the night that the Princess of the Sun was trapped within the Princess of the Moon.