Pony Anatomy Transformation

by Bendy

Rating: mature
Tags: Sex, Human, Twilight Sparkle, Anon, My Little Pony: Friendship is Magic, Second Person, Rainbow Dash, Romance, Princess Luna, Comedy, Random, Princess Celestia
Length: 3571

Rainbow's and Twilight's bodies undergo a strange transformation. The two aren't very happy about the changes. Meanwhile, Celestia, Luna, and Cadence struggle to resist you.

Rainbow's and Twilight's bodies undergo a strange transformation. The two aren't very happy about the changes. Meanwhile, Celestia, Luna, and Cadence struggle to resist you.

A big thanks to my editors: forestpip and Jay The Stormtrooper

Published 2017-02-01 17:50:01 UTC
Last updated 2017-02-01 17:50:01 UTC

Anatomy Changes

“Nooooooooooooooooooooooooooo!” Cadence screamed, struggling in vain against the stronger and bigger alicorns, known as Celestia and Luna, dragging her out of the room.

Once they managed to take her out of the room, Celestia lit up her horn and quietly shut the door behind them with a soft click. This left the room with only you and the two other alicorns, Rainbow Dash and Twilight Sparkle, on the bed. A long awkward silence ensued, all three contemplating over the events that had transpired.

“Well, that was fun!” Exclaimed Rainbow, clapping her hooves together. “Let's go get breakfast!’

Rainbow hopped off the bed, trotting her way over to the door. Twilight soon joined alongside her. When you did not move, both of them turned to look at you curiously.

“You cumming— I mean, you coming Anon?” Asked Dashie in a soft tone.

Just when you were about to open your mouth in reply, there came a flash of light behind both Rainbow’s and Twilight’s backsides. The two mares exchanged looks, before turning to look at each other’s rumps.

“Ewwww, Rainbow! There are two holes in your butt!” Yelled Twilight Sparkle.

“Yours too! They look disgusting!” Shouted Rainbow, sticking out her tongue.

“What are you—” your words died in your throat when they turned around to show a most unexpected sight. “Awesome! You’ve got vaginas and assholes now!” You shouted excitedly, your long and thick cock even while flaccid twitched hard, beginning to slowly rise.

“How can you like them Anon? They look so horrible,” Asked Twilight in a most bewildered tone.

“How could a human ever want to cum inside something so awful looking?!” Exclaimed Rainbow with her hooves raised high in exasperation.

“Ladies, the penis never lies,” You said with a smug grin, pointing down at your slowly rising cock.

At the sight of your hardening dick, they came flying toward you at lightning speed, pushing you over onto your back. From there they kissed your cock on the thick tip at the same time, making you utter a loud groan. The mares made loud excited horse sounds whilst kissing, licking, and rubbing their soft hooves along your cock as it grew in size, becoming hard and throbbing with power.

Each lick, kiss, and rub helped your cock swell larger and larger in size, filling up with blood and its thick veins pulsing with power, preparing your mighty penis to make sweet love to, or possibly destroy, these little ponies’ pussies and assholes.

Inch by glorious inch your behemoth cock grew bigger by each passing second, becoming longer and thicker as both alicorns lovingly helped it to quickly reach its full mast to become a monstrously large, horse-cock-sized penis in human shape. Now, if anything, it looked even bigger than before.

Twilight stared wide-eyed in horror before an even more massive cock than she remembered, Rainbow, on the other hand, looked quite pleased, licking her lips at the sight of it.

Your legs jerked violently when Rainbow opened her muzzle wide, quickly dropping her head to bring her mouth down to reach her previous mark, only for her mouth to stop halfway this time. Your thick tip rubbed against the back of her throat at merely about a quarter and a half way down your long shaft.

A heated growl left the alicorn, the growl reverberating around your cock as she glared hatefully with narrowed eyes down upon your dick.

“Please, don’t bite it Dashie,” You spoke in a pleading tone, a look of worry filling your eyes.

Rainbow stared up at you, to give you a look of hurt and betrayal behind those large, adorable, rosy red eyes of hers. Her eyes alone told you she would not even think about ever doing that to you, despite the fact her mouth could not reach further down than before over your cock.

“I’m sorry Dashie,” You said softly, reaching a hand down to briefly scratch the back of her ear.

Rainbow’s lips curled up around her mouthful to form a small smile, her eyes flashing with love hearts. The mare then made a strong swallowing motion, squeezing your thick tip in the back of her throat. This caused you to utter a low grunt and her to make a giggle from around her mouthful.

Her next move took you by surprise. Rainbow slowly lifted her head, rolling her soft lips along your shaft. When she eventually reached the tip, she made the long descent downward to reach her previous mark, still very far from touching the base and not even reaching halfway.

Reluctantly, she slowly lifted her head back up, before gradually making her way downward, and doing the same again when she reached the bottom. Soft moans and quiet horsey sounds left the alicorn mare while she sucked you off.

Blissful sighs left you over and over again, loving this strange, slow affection from the usually fast-paced mare. You felt relaxed, enjoying the warm, soft and wet muzzle of Rainbow gently sucking your cock. Your release seemed quite far away, but you didn’t really care. You were content to just relax and enjoy Rainbow’s slow and gentle blowjob.

Lazily, your eyes shifted over to Twilight, wondering why she was so quiet. You got your answer by the look of fear in those big purple eyes of hers, her body trembling.

“Twilight… what’s wrong?” You said softly, wrapping an arm around her barrel, pulling her close to your chest.

“Your…. your…. your penis. It scares me,” Said Twilight in a low voice.

“Twilight, you don’t have to have sex with me if you’re too scared. But if you do, I promise I will be even more gentle than the first time you got love cuddles from me,” You said softly.

Twilight sighed in relief, laying her head down on your chest. You closed your eyes, content to just lie there cuddling Twilight and getting your dick slowly sucked off by Rainbow.

‘I hope this thing doesn’t get any bigger. Because it’s getting a bit ridiculous now,’ you thought bitterly.

For quite awhile nothing eventful happened. You merely lay there holding Twilight close to you and getting your giant dick sucked off by Rainbow.

Until Twilight broke the silence by uttering a hiss of pain. This, followed shortly with Rainbow using great speed to lift her head off your cock.

You opened your eyes to see the purple alicorn in a most distressed state, she was biting her lip and bullets of sweat were pouring down her forehead. Rainbow between your legs too was sweating and biting her lip.

“Anon, my vagina feels painful,” Twilight whined.

“Both of my holes hurt!” Exclaimed Rainbow.

Your face became pale and your dick became a little softer. “Oh god, don’t tell me you need to use the bathroom?!” You exclaimed.

Twilight and Rainbow nodded wordlessly in answer. At this your cock began to rapidly shrink at the horrors of the revelation.

“Oh, fuck my life,” You said in a low voice, burying your face into your hands.

“Could you help us use the bathroom?” Spoke Twilight, in a soft voice.

You slapped your forehead. “Okay, but only this one time! I don’t want to watch you pee and poop every day! You’ll kill my boner for life!”

Rainbow Dash gasped in shock. “We can’t have that!”

“Just tell us what to do!” Said Twilight.

“Open a window, sit on the toilet and release your body waste. And make sure you flush the toilet firmly and clean your butt with toilet paper or magic until there’s no brown stuff or your liquid left, flush that down, spray some air freshener, and then wash your hooves well.”

“Got it!” Said Rainbow saluting you, before flying out of the room, along with Twilight trotting after her.

You sighed in relief, over being saved from the fate of having to endure the horrors of potty training.

For a moment nothing happened, the only sounds you heard were the chirping of birds. Before you heard the two mare scream in terror.

“Aaaaaahhhhhh! Sweet Celestia save us! It’s a smelly abomination!” Screamed Twilight.

“I think I’m going to be sick!” Shouted Rainbow.

You uttered a groan and put your hands over your ears to block out the sound. Your cock was now completely flaccid after hearing that.

Suddenly, the door burst open, followed by Celestia, Luna and Cadence rushing inside.

“We can’t resist it any longer! We demand to suck thine penis!” Boomed Luna in a deafeningly loud voice.

You pulled the blanket over you, covering your penis.

“Get that ass clean! Anon needs help!” You heard Twilight shout from next door.

“Almost done!” Shouted Rainbow.

“Luna! Sucking this human’s penis is a delicate matter! We must approach this diplomatically!” Said Celestia in a stern voice.

“YES! Indeed! We must earn his trust to suck his penis!”

“I wholeheartedly agree,” Said Cadence.

“Uh, ladies. I’m scared. I’m not sure if I can trust you,” Came your voice, low and nervous.

“Trust in us handsome ape! For even if we were Nightmare Moon before you, we would never hurt thine penis!”

“How would you know. What if she—

In an instant Luna transformed into a pitch black alicorn, who had a fearsome steel helmet, along with sharp, carnivorous teeth and roared in a deafeningly loud voice that was so powerful the building began to shake. You and everyone else put their appendages over their ears to block out the sound.

“LUNA IS CORRECT! EVEN WE WOULD NOT HURT THINE BEAUTIFUL PENIS! WE WOULD SUCK THE PENIS MOST GENTLY! AND EVEN CAST A BLUNT SPELL UPON OUR RAZOR SHARP TEETH TO MAKE SURE WE COULD NOT HARM THY PENIS!!!!!!”.

A moment later, Nightmare Moon was gone and returned to Luna, who was smiling nervously with a bright red blush upon her cheeks. “Sorry, she takes control sometimes,” She said in a low voice.

There came the sound of a flushing toilet, soon followed by Rainbow and Twilight flying into the room, rushing over to land on the bed beside you.

“Leave him alone! Only we can suck his penis!” Roared Rainbow, raising her hooves like as if she had fists.

“Yeah! You could hurt him! You big bullies!” Roared Twilight, flapping her wings.

“HERESY! How could thou not share his penis?!” boomed Luna, stomping her right hoof, creating a huge crack in the floor with her super alicorn strength.

“Okay-okay!” you shouted. “I’ll allow one of you to suck me off today.”

“Oh! Pick me! Pick me!” Cadence shouted excitedly, jumping up and down.

“NONSENSE! The handsome ape shall pick me!” Luna roared, giving a hateful glare to the pink alicorn.

“I choose Celestia.”

Celestia made a happy sound like a dog’s chew toy and a broad smile came upon her face. Luna and Cadence growled angrily at this turn of events.

“You chose poorly human. I’ll have you know I am the most top rated pornstar of Red Hot Cuddle Whorses magazine!” Said Cadence in a most disappointed tone.

“And we have had far more love cuddles than Celestia,” Said Luna in a sour voice.

With that Luna and Cadence trotted out of the room, grumbling bitterly.

“I promise, I will be most gentle Anon,” Spoke Celestia in a soft voice.

The large alicorn stepped forward toward the bed. Once there she turned around to lay herself down, forcing you to shift over to the bed’s edge from her sheer size, possibly your body a mere inch away from falling over onto the floor beneath. Additionally, Twilight and Rainbow were forced to leave the bed entirely to make room for the big mare.

“This bed is a little small for me. Do you mind if I sit on your face?”

You gulped in terror at the sight of the massive, white bubble butt lying next to your head, its sheer size casting a dark shadow over you. “Uh Celestia, please don’t be mad. But do you have any weight protection magic? Because I think you will kill me if you sit on me.”

Celestia sighed sadly. “You’re right, I’ve been going heavy on the cake as of late.”

Her horn flashed with golden light. For a brief moment, you felt a slight tingling sensation course through your body.

Celestia stood up, her huge form casting a huge shadow over you. You could not help but shake in fear and feel insignificant before her large size. She waited for you to shift your body over into the middle of the bed before she proceeded to gently sit herself down upon your face.

Darkness took you as you became lost in the abyss that was Celestia’s ass. Her heavy, massive rump pinned you to the bed, completely immobilizing your head from under her immense, oppressive weight.

Immediately, you began licking the featureless canyon of her backside, earning no reaction from her.

Thankfully, your arms were free. So, you used them to reach around her to squeeze her massive cheeks, sinking your hands deep into the thick layers of squishy, soft fat from her huge rump. You repeatedly squeezed those massive mounds of flesh together to your heart's content, loving the feel of her ass’s soft, flabby flesh being pushed back to your touch.

You could only guess you were holding onto her cutie marks, or at least a part of them. This mare’s butt was quite a big thing after all. Somehow, you were still able to breathe from under this big pony butt prison.

Slowly, your cock began to rise to attention. Muffled moans left you when you felt Celestia leave a gentle lick upon the very tip of your cock.

She uttered a loud, whinny in excitement, loving the sight of your growing cock. The white alicorn mare began leaving a series of soft kisses and tender licks all along your shaft, encouraging your dick to rise faster. Celestia giggled happily from hearing your muffled moans beneath her enormous ass.

When your cock came to stand at its full, mighty height, she took a deep breath, opening her mouth wide, before ever so slowly taking your thick tip into her maw.

A loud grunt left you, Celestia made low moans and quiet horse sounds as she began to slowly take more and more of your cock into her muzzle. Her plump, soft lips felt amazing, her thick, large tongue felt incredible for your cock to roll against as her mouth made the long journey downward.

When she reached the quarter and a halfway mark she kept going, soon reaching the halfway mark and quickly surpassing that to go even lower.

Twilight and Rainbow looked on in amazement with their jaws dropped as Celestia seemingly without any issue took more and more of your massive cock into her mouth. Your legs began kicking weakly, overwhelmed with pleasure from the feeling.

Eventually, the white mare reached the very bottom, her thick lips kissing your hefty balls and your thick tip was now all the way in the back of her long, swan-like neck.

Celestia hummed around her mouthful, making a powerful swallowing motion. Your screams of pure ecstasy were muffled by the immensely thick layers of soft fat from beneath her massive butt.

“Hey Celestia, if you keep sucking on it for hard enough for a bit his penis will release tasty creamy stuff,” Said Rainbow in a menacing voice, an evil grin on her face.

From hearing that Celestia uttered a loud, excited whinny before quickly raising her head up to the tip of your cock, followed by dropping her head back down to take your cock into the back of her throat again, and then rapidly rising her head back up and doing the same again.

Celestia quickly bobbed her head up and down your long shaft, determined to get your seed unleashed. You moaned aloud into the thick mass of flesh above you, your shaky hands grip on her rump felt weak. Your defenses were shattering into smithereens before her deadly oral attack.

Loud slurping, your moans of pure bliss and quiet horsey sounds filled the room. Twilight and Rainbow looked on in awe, rubbing a hoof upon their lower back each, moaning all the while.

Celestia jerked her head up and down your cock without stop. Soon, a tingling sensation coursed through your rod, signaling your impending release.

You uttered a loud groan before breaking the dam. Thick spurt after spurt of your seed shot into her mouth, her cheeks rapidly bloating out from the sheer volume of your release. Celestia moaned aloud, squeezing hard upon your cock with her mouth, she wanted more of your cum, even while you still were not finished releasing.

Her cheeks thickened outward, struggling to contain the massive quantities of your cum being unleashed. The mare made a loud, audible swallowing sound.

Celestia gobbled down your spunk again and again, each hard pump of your cock releasing another massive load of creamy cum into her mouth. A full minute went by, and you were still not done cumming.

With a tight seal over your shaft, she began to bob her head up and down your cock as it continued to feed her wave after wave of your cum. Up and down her head went, her lovely muzzle squeezing hard upon your cock in an attempt to make it release more cum into her hungry mouth.

Your cock answered her, pulsing powerfully with renewed vigour to begin unleashing like a fire hose. Your screams were muffled into her massive ass, your cock wildly thrust upward into her loving mouth. Celestia was lost in her own little world, giggling and moaning aloud as she hungrily devoured your seemingly endless amount of cum, gulping it down with gusto, making loud swallowing sounds as she did so.

Your heart was beating hard in your chest, the pleasure was too much, you became fearful of actually dying from your heart giving up.

On and on your cock kept feeding her your creamy goodness seemingly without an end in sight. Celestia, with love hearts flashing through her eyes, moaned like a bitch in heat and made loud horsey sounds, worshiping your cock with her mouth and never seeming to quench her hunger for your cum.

Such was the quantity of your seed being unleashed into her, her belly began to slowly expand in size. This made Twilight and Rainbow take a step back. Thankfully, Celestia’s belly stopped expanding before things could go totally out of control, and your penis gave one last thick glob of cum into this glorious pony’s gullet.

Celestia uttered a disappointed whine when your cock stopped feeding her.

The mare began bobbing her head up and down your cock, trying to make it hard again so it could feed her some more. Alas, despite her best efforts your cock merely continued to become softer and shorter within her mouth.

She sighed sadly, before she slowly lifted her head to release your member with a loud pop.

“I know what cream I’m going to use for my cakes in the future,” She beamed happily.

Suddenly, there came a flash from Celestia’s backside.

“Hmmm, my butt feels weird,” she said in a most bewildered tone.

Down below, beneath the heavy, thick mass of Celestia’s butt an evil grin came upon your face. A strong source of heat emitted off her ass now, smelling faintly of vanilla.

Without warning, you licked what you believed was her vagina. You moaned in bliss at the sweet whipped cream flavor of her juices. The snowy white mare uttered a loud, animalistic neigh in response from the strange, yet wonderful feeling coming from her butt.

“Oh, that felt nice. But what has happened to my butt?”

“You must have gotten a vagina and an asshole,” Said Twilight.

“A what?!” she exclaimed. Twilight smiled nervously, before turning around to show her exactly what she was talking about. “Sweet me! What is that horrid thing?!”

Twilight lowered her head in shame, some tears falling down her cheeks.

“Oh Twilight, I’m sorry. It doesn’t look so bad,” She said softly.

“Don’t worry Celestia. Anon likes them and that’s all the reassurance I need.”

“Anon likes those? I must see this for myself,” With that, Celestia lifted her rump off your body and showed you all her assets.

Between the wide expanse of her massive mounds of perfectly round flesh belonging to her enormous bubble butt, there was a delicious plump, wet marehood, with a thick donut asshole above it.

“Yep, I love your big fat ass!” You said sexfully, your cock already beginning to re-harden

“Hey, I’m not fat!” she growled.

“Celestia, you are a big, beautiful, meaty mare. And I love meat on my woman.”

Twilight and Rainbow growled angrily. This made you gulp in fear.

“And I love your butts too girls!” You shouted.

“You better!” Exclaimed Rainbow.

“I only wish this dick wasn’t so big that it could really hurt your vagina,” You said in a low voice.

“What do you mean Anon?” Asked Twilight in a curious tone.

“You see--” Suddenly Twilight’s and Rainbow’s bodies shot up to become just as tall and nearly as big as Celestia’s, but Celestia’s butt was still quite a bit bigger. ”Well, that was convenient.”

“That penis of yours sure is doing some weird ass shit to us Anon,” said Rainbow.

The End