Fillyestia

by PeachStrudel

Rating: teen
Tags: Princess Celestia, Princess Luna, My Little Pony: Friendship is Magic, Alternate Universe
Length: 3140

Warning: This story contains diapers, diaper usage, and AB/DL themes. If these do not appeal to you, then please do not read any further. | Princess Celestia takes her usual trip to the Fountain of Youth, but accidentally falls in.

The story in which Celestia falls into the Fountain of Youth and Luna tries to take care of her. Age Regression, Diapers, Wetting, Messing, and Babying ensue.

Special Thanks:
LPHooves - Editing and Cover Art
Der-Fuhrer - Editing
#diaperponies on irc.rizon.net - General tips and pointers

Published 2014-11-06 03:00:03 UTC
Last updated 2014-11-07 01:08:39 UTC

The First Funky Chapter

Author's Note

Hold on there Jethro! You're about to read a chapter that's actually a little sad at first! There's some implied Age Regression in here too, so if that don't float your boat, turn back!

The First Funky Chapter

"I believe it's coming to that time of the decade again, dear sister." Princess Celestia groaned.

"Already? It seems only yesterday you last visited the Fountain." Princess Luna responded.

"It seems like I've had need of it more frequently, doesn't it?" Celestia said, arching a brow.
"As long as it still gets rid of these aches in my joints, I don't mind."

"Very well, I shall hold down the castle as you make your trip during my night, sister."

"Thank you, Luna."

———

Princess Celestia sighed longingly, deep in thought. I sometimes wish I were not in charge of Equestria. Then perhaps my journey to the Fountain wouldn’t be every few years. Celestia shook her head, clearing her mind of the selfish ideas.

She was ready to begin her trip to the Fountain, not that it required much physical preparation. It lay hidden in the crystal caves beneath Canterlot, nestled behind a wall of sapphirine gems with only the most imperceptible crack. The only clue to the treasure hidden within was the sound of the ever-flowing water of the Fountain should one press their ear against the fissure.

Celestia flew to the entrance of the caves, finding herself contemplating again the same troublesome thoughts that each trip brought. Such a blessing and yet a curse to bear, knowing of Canterlot's best kept secret. Why must I watch the ponies I care for find peace in death, yet I am ever needed in this mortal plane? She shook her head again, reaffirming herself in the truth that, without her and her knowledge, pony society would crumble and evil forces would plunder her beloved nation. She knew this responsibility could not merely be shrugged off. Thankfully the same is not true of my tiredness.

She steeled her nerves and entered the cave, the ever present damp of the underground greeting her. As she lit her horn alight, she glanced passively at her reflections in the crystals. She trudged through the twists and turns of the labyrinth, recalling the times she explored the caves with her sister. It seemed so long ago such young sisters had managed to spin the lie that they were deities unable to die; the eternal rulers swearing to never leave Equestria’s side as joint rulers.

Celestia soon stood before the all too familiar crack in the crystals, carefully placing her ear against the crack. She listened for the sound of the water, which called as loud and true as the first day. Her horn glowing, she cast the teleportation spell to pass the crystal wall. Once there, the Fountain’s majesty humbled her anew. The clear water shimmered, seeming to give off a faint glow, unnaturally illuminating the otherwise dark section of the cave. It looked just like the fountain in Ponyville square.

She smirked, greeting the Fountain in her mind. Hello, Fountain of Youth. I've come to visit again. It's been too long. How have you been? She laughed a bit; talking to the Fountain as an old friend. As she thought the conversation through, she began to approach the waters.

However, her approach faltered. Her hoof struck a crystal jutting out of the ground, casting her ornamental horseshoe to the side and tangling her steps. Luckily, she was able to catch herself before tumbling into the Fountain. Phew, that would have been bad. I don't dare think what would have happened were I to fall in... She sighed in relief and continued her approach. She levitated a small, unastounding cup she had brought and dipped it into the Fountain. The cup filled to the brim, she brought it up to her mouth and gulped it down. The refreshment was nearly instantaneous, her aches beginning to dissolve and her coat regaining its brilliant white sheen.

Ah, that feels so nice. She turned around with renewed vigor and trotted back towards the wall hiding the Fountain. Or, as fate would have it, she would have had she not slipped on her horseshoe that fell off earlier. She reeled backwards and fell into the Fountain with a large splash. Her calm composure was all but gone, panicking and clenching her eyes as she scrambled from the smooth interior of the fountain. Crawling out and tumbling onto the crystalline floor, she shivered in the cold wetness and the dark of the cave. The soft glow of the water in her coat faded and she was left dark.

Celestia rubbed the water from her eyes and slowly opened them. The world was much bigger than it was a moment ago.

Oh no.

Chapter the Second

Author's Note

You've made it to the second chapter, good job! I must warn you, there's a little squicky stuff in this one such as peeing and the mention of diapers. If you've got the patience, read on and the good stuff will be coming soon!

Chapter the Second

The cave felt even colder, the cold biting through Celestia’s sopping wet coat, mane, and tail. She shivered and groaned softly. A long unfamiliar voice echoed through the cave. She stepped over to the wall that kept the Fountain a secret for so long, confirming her fears in the reflection. I’m… I’m a young filly… She looked over herself; she couldn’t have been taller than a foot and five inches. Her mane and tail were a bright pink and no longer flowed like her older self. She looked like a normal filly. Luckily, she still found her cutiemark.

She shuddered, closing her eyes. I have to get back to Canterlot. Her horn lit up and sparked as she again attempted to teleportation through the crystal wall. Depsite all her might and concentration, she couldn’t pull it off. Her body must have been weakened by the change. Young fillies don’t have the physical means of controlling their magic, after all. She whimpered instinctively before catching herself. No, I’m stronger than this… I just have to contact Luna. She can get me out of here. Once again, she gathered all her strength and reached out telepathically to her sister.

“Lun-...-an you-...-me?”

Luna flinched at the sudden voice in her head. She was in the middle of her Night Court when she heard the familiar voice of her sister. Something was unusual about this time, the usual strength and clarity of her sister’s voice not shining through. She knew something had gone wrong. Her sister never had trouble communicating with her before, even in the deeps of the crystal caves.

“Night Court adjourned! We have important matters to attend to!” Luna was already out of her seat before the guards and ponies lined in front of her throne could process this declaration. They looked at each other, confused and worried by the Princess’s sudden change in demeanor. Luna walked quickly through the main door and out towards the castle gates. She spoke to the guards at the front. “If We are not back within the hour, send a search party down to the crystal caves. That is all.” The guards looked at each other and then back to Luna, nodding in agreement.

Luna traced Celestia’s arrival to the cave, growing more worried with every passing minute. She rushed through the long-memorized twists and turns of the caves and soon arrived at the sapphire wall she feared her sister had been trapped behind. With a quick teleportation spell, she was on the other side, looking around frantically for her sister. Luna gasped as she saw Celestia’s horseshoe on the ground, soon finding the pile of her royal raiments.

“Sister! Sister, where are you?!” Luna shouted.

“Not so loud, dear sister. I’m… I’m down here.” Celestia responded.

“Down… here?” Luna asked, a bit puzzled by her sister’s choice of words. Then she looked down. Luna put a hoof to her mouth as she saw the now much younger version of her sister. “W-What happened?”

“I slipped an’ fell into the Fountain.” Celestia put her own hoof to her mouth, eyes wide. She realized that a slight lisp had come with her new body.

Luna hid her smile well, not wanting to upset Celestia. “Well, we should get back to the castle. Perhaps something in the royal library can help us find a solution to this… predicament.”

Celestia tilted her head and offered a rebuttal. “While I would be glad to do so, how would we esplain this to the guards?”

Luna tapped her chin with a hoof. That was quite a problem. They couldn’t just tell the guards that there is a Fountain of Youth under Canterlot. Then an idea struck. “Magical backfire. Every unicorn knows that holding back a spell for too long can have any number of detrimental side effects. This one just happened to be age regression.” Luna smiled as she spoke her thoughts.

Celestia thought about this reasoning for a moment. It sounded believable at the least, and really, it would be their only way to keep the secret of the Fountain secure. “Very well. That is our escuse.” She nodded in agreement.

Luna used her magic to levitate Celestia onto her back, nodding in affirmation. “Then it is agreed. Now, let us return to the castle.” Luna hummed. She teleported the two of them through the wall again and made her way back out to the dark night of Canterlot. Luna flew them both back to the castle, presenting their explanation to the guards without any questioning.

As Luna was carrying Celestia to the royal library, she noticed a warm sensation dripping down her back. Startled, she stopped in her tracks. Celestia tilted her head, looking confused.

“Why did we stop?” Celestia asked.

“S-sister… we think you are urinating on us.” Luna stammered.

Celestia’s face flushed a bright red as she looked down to see herself trickling pee onto her sister. She shot her forehooves down and pressed them against her crotch, but the flow had already stopped. “I-I-I…” She stuttered.

Luna took Celestia off her back and shuddered. “Your body must be regressed more than we thought.” Celestia hid her eyes behind her forelegs, utterly embarrassed that she had an accident on her sister. Luna gently pushed Celestia’s legs out of the way and looked into her eyes. “It is no consequence, sister. Do not be ashamed. We should have foreseen your young body being unable to handle such stress without consequences. Do not worry.” Luna said, trying to comfort her sister with an unusually soft voice.

Celestia seemed to take offense with Luna’s tone. “H-hey, I’m not actually a filly. I still have my mind.” She huffed.

Luna shrugged. “Really? I would not know that considering how you are acting.” She retorted.

With a sigh, Celestia relaxed. “You’re right; I need to pull myself together. I’m sorry, sister.” She apologized.

Luna smiled. “It is alright, sister. However… we do fear this complication will happen again. Would you mind if we took some precautions?” Luna questioned.

Celestia arched a brow. “What sort of precautions?”

Luna sighed slightly, knowing that her sister would not be happy with her suggestion. “I think we should put you in protection.” Luna stated.

Celestia nods. “That sounds alright. We wouldn’t want anypony to harm me while I am in this state.” She added.

Luna looked away from her sister. “I-I meant a different kind of protection… Diapers.”

Trio the Chapter

Something has gone wrong. We don't seem to have an archived copy of that chapter.

The Fourth Installment

Author's Note

Oh man you guys, things are starting to happen! Well, not really. Anyway, keep on keepin' on. There's more where this came from.

The Fourth Installment

The night went on, dreamless like every night. With a small yawn, Celestia woke to the sunlit balcony pouring light over her blanket covered frame. She pulled the blanket up, over her head, not yet wanting to leave the comfort of sleep. However, the blanket caught under her padded rump and pulled against her diaper with a squish. Her eyes bolted open and she cast her blanket up and behind, only to meet with the sight of her now equally illuminated and equally yellow diaper, cold and clammy against her fur. I really have lost control… great. With an upset sigh, she took the blanket and pulled it back over her body, covering the diaper. It was then that her eyes widened, met with her new surroundings. White wooden bars enveloped her safely.

She quickly realized Luna had put her in a crib for the night. Tears welled up in her eyes but were quickly suppressed and wiped away with a forehoof. She refused going to cry, not for the lack of the desire, but merely to spite the scene of her being a foal. A deep breath later, she regained her composure and stood onto her hooves. A considerable waddle in her step, she trotted to edge of the crib and stood up on her hind legs, looking over the side, when something caught her eye. A finely embellished baby monitor sat in the corner. Luna must have put that there so she would know when my sleep ended.

As if on cue, Luna knocked on the door to her sister’s chamber. “Celestia? Is it alright if I enter?” She asked.

“Yes, you may come in, Wuna.” Celestia lisped.

Luna entered, wearing light blue saddlebags, and closed the door behind her. She approached Celestia, noticing the swollen diaper. “Oh, it appears you’ve had another accident in your sleep,” she spoke softly.

Celestia looked unimpressed by her sister’s observation. “Fanks for remindin’ me.” she said, “Wha’s in da bags?”

Luna walked over to the crib and levitated her sister from it. “We have come prepared for this eventuality, dear sister.” Luna stated rather triumphantly, proud of her foresight. She used her magic to lay out a thin plastic changing mat on her sister’s dresser top. Wipes, powder, and a fresh diaper quickly followed. “Are you not glad that we have saved you the embarrassment of a wet bed?” Luna queried.

“I suppose so. Jus’, pwease make it quick. Dis is gettin’ uncomferble,” Celestia groaned. Luna nodded and laid her sister on the mat, quickly getting to work. The tapes were popped in succession and the diaper rolled up and set aside with a squelch. She worked quickly, minimizing her sister’s embarrassment, wiping and powdering her. She slipped the fresh padding under Celestia’s rump and taped it snug to her waist, carefully threading the small tail through the hole. The used diaper was then tossed in a nearby bin.

Celestia didn’t close her eyes this time, instead blushing profusely as she stared at her sister’s face. To think, that my younger sister would be the one changing my diapers. How absurd! Her rear freshly padded, she sat up and shook her head. “I appwisiate yow help, Wuna.”

“Of course. Now, let us go get something to eat,” Luna suggested.

“Tha’ sounds wike a good idea,” Celestia smiled. Soon after finishing their meal in the dining hall, Luna couldn’t help but be troubled by a certain fact.

“Celestia, we have a slight suggestion,” Luna stated, a bit uncertain.

“Yes, sister? Wha’ is it?” Celestia wondered.

“Hmm… we believe it unwise to attend your court this day. We are not certain how the citizens of Equestria will respond to their leader being, well… a young filly.” Luna suggested, looking worried. “Our uncertainty is made more so by your current attire.”

“I s’ill have my dudies, and nothin’ can stop me,” Celestia stated, “The pubwic will not see me diffwently. Anyway, s’only tempowary.”

Luna nodded. “It is your right, sister. It is almost noon. Your court begins in fifteen minutes.” She informed.

Celestia flattened her ears. “Then we mus’ go. I sh’uld be earwy.”

Luna agreed, levitating her sister onto her back. Luna quickly travelled through the halls of the castle and soon arrived at the Sun’s Court. Luna set her sister in her throne. “We will arrange for the guards to bring you to us at your duty’s conclusion. We apologize, sister, but we must sleep as well. Good luck. Ah, and do not be afraid to punish any disrespect.”

Celestia nodded, steeling her nerves. The clock struck noon and Celestia looked to her attentive guards. “Send the pubwic in. I am weady.” The guards nodded, successfully hiding any worries they personally held, and opened the doors of the hall. The first ponies in the line approached the throne. The front one, a blue pegasus stallion, stopped as he saw the small filly on the throne. He turned to the guards and received their nods, silently telling him that the diapered filly, lacking any regal adornment, was indeed the Celestia they all had come to see. “Gweetings, loyal subjec’. What is your declawation?” Celestia said with as much authority she could muster.

“U-u-uhm, yes, you see…” The blue pegasus stammered and stuttered his way through his declaration, taking about thirty minutes to fully get out what he came to say.

“Very well, your concewn abou’ the state of da enviwonment has been noted and will be taken into considewation. Fank you for visiting today.” Celestia stated, successfully hiding her exasperation at his inability to properly present his declaration. The pegasus bowed shakily and nearly jogged out of the court. After passing the corner he peaked his head back through, making sure he had indeed been talking to a filly sized Celestia and had not hallucinated the experience.

As the court went on, a third of the ponies in the rear simply left after reaching the throne. They usually excused themselves to turn off forgotten ovens or promised to return later. Celestia was confused at the later change in the citizen’s behavior. The first ponies had no problem presenting their declarations besides their unease. She wondered if her beloved ponies of Equestria were scared of angering her in this state. Her mind screeched to a halt as she took a deep breath. Her pupils shrank. She smelled a pungent odor, and had an assumption of the source. She shifted in her seat a little, only to confirm her thoughts. A gross mushing sound echoed through the emptied court, her guards standing silently at their posts.

The two throne guards turned to see the source of the sound. One of immediately looked away and the other managed to keep composure. The latter asked a simple question, “The court is over now as it is six o’clock. Would you like to be escorted to Princess Luna, your majesty?” Celestia nodded, trying her hardest to keep from crying. She had messed herself in front of her subjects without any indication or warning.

I will never live this down...