You the human, dressed in a fine, black tuxedo walked along a white marble hallway. You were flanked on both sides by two very large equines. Both of them possessed feathery wings upon their backs and long pike-like horns atop their heads. They didn't look like equines from your old world. For one thing, they had comically large eyes and had magically flowing manes, which blew in an unseen wind.
If you were to compare their size to anything they were basically elephants in the shape of horses. The dark blue one, on your left, stood at about ten feet tall or so. While the even larger alabaster one stood at about fifteen feet tall.
You became nervous at the size difference between you and them. You weren't sure this threesome with Princess Celestia and Princess Luna was a good idea anymore.
But then you remembered you were so desperate for sex that you will be willing to have sex with these giant ponies even if you couldn't adequately please them. Besides, it was they who asked you. They would have to be idiots to think you had a penis big and strong enough for them.
The three of you approached a large double golden door. Without a word, they magically opened the door. Your eyes widened at the sight of what seemed to be a white void within the door.
The two walked into the ‘room’, their hooves clopping lightly against the invisible floor. It sounded like stone, but there didn't seem to be a floor. Cautiously, you peered your head into the room, while still staying out of the room, your feet not touching the white ‘floor’.
You looked around the room to see nothing more, but more white emptiness.
“What is this place?” you asked.
Celestia leaned down to look at you at eye level, before speaking softly to you. “It’s a room we created for me and my sister to safely unleash the true power that’s inside us.”
“What true power?”
“This power.” replied Luna in a deep breathy voice, turning around in quick succession, and then she leaned forward to raise her massive ass high into the air before you.
Her cutie marks flashed with blinding light. She inched up higher and higher into the air by the second. You looked on in both fear and fascination as she grew in size before you. Her rump air ballooned outward, her legs below rapidly grew thicker and thicker to help support her rapidly-swelling rear end. Her hips truly became monstrously large, only growing bigger and bigger by the second – growing in size alongside her ass made her look absolutely breathtaking.
When Luna finally stopped growing, she had grown to be at least three times larger. She now stood at an imposing thirty feet tall. The cheeks of her rump were now like blimps.
“Is our rump to thy satisfaction for the moment?” she asked, staring back at you with bedroom eyes.
“Umm, Luna you're very pretty I’ll give you that. But how am I supposed to sexually please you?”
“Worry not little one. Thou shall sexually please us by being sat on by our royal posterior.”
Your eyes widen in alarm. “Ummm, I don’t want to be crushed to death.”
Celestia gasped in shock, her eyes narrowed into a hateful frown.
Luna's jaw dropped at what you just said. Her lower lip began to quiver, and tears began to form in her eyes. And she… even started to rapidly shrink down in size. In a manner of seconds, Luna became a mere four-foot-tall pony.
Being at such a reduced size seemed to have upset her even more. She uttered a loud wail of grief, and lay herself down on the floor and covered her face with her hooves. Whatever you did seemed to have hurt her feelings to the point it made her smaller.
“Don’t look at me! I’m so bony thin and small now!” she screamed.
“Anon, apologize to my sister immediately!” boomed Celestia.
Well, you were dead either way, so you might as well take your chances. You walked into the room and sat down in front of Luna.
“Luna---” you began softly.
“Don’t speak to us! Vile ape!” she boomed, looking up at you with a hateful glare.
You looked into her eyes, seeing how bloodshot they were and the look of hurt behind them.
“Please Luna, I’m really sorry. You scared me. I'm not some superpowered being like you. I am small, frail, and mortal.”
The mare crawled up to you and lay herself down on top of you. The look of hate in her eyes had vanished, replaced with a look of concern.
“We are sorry too Anon. We shouldn't have started our growth magic so strongly. We thought that thou would go insane with lust at the sight of our body augmenting in size. We are so used to seeing our Royal Guard bowing before us and worshiping our royal posterior, that we didn’t think thou would react any differently.”
“Your guards don’t fear you?”
“Of course not. Our bodies never harm the innocent, no matter how big they get. We even show mercy to the wicked. We facesit on them into submission until they change their wicked ways.”
“Are you sure this is not just going to motivate people to be evil If it gives them a chance to be facesitted on by you?”
“Somewhat yes. I know from experience.”
“You were once evil?” you asked.
“Yes, we were once Nightmare Moon. Thankfully, my sister saved me by facesitting on me until I turned back into Luna. Nightmare Moon could not stand against the power of our sister's rump.”
“How did you defeat Nightmare Moon with your butt?” you asked, turning to Celestia.
“We are the goddess of the sun, while our sister is the goddess of the moon. We naturally grow much faster than her, Plus, I used the power of the Elements of Harmony on my own backside, and my love for my sister only increased the strength of my growth rate.”
“Do you get jealous that your sister grows faster than you?” you said, turning to Luna.
“We are ashamed to admit it but yes. Part of the reason that we became Nightmare Moon was over our jealousy of our sister’s much greater growth rate than us.”
Tears began to fall down Luna’s cheeks, overwhelmed with emotion as she spoke in a soft voice. “My sister told me that her body could grow to consume the entire universe and beyond, but without the company of the Moon alongside it, it would lose its beauty. It was those words that defeated Nightmare Moon.”
“I love the story. But can I behold your glorious asses now?” you said, placing your hands on Luna’s buttcheeks. Your hands sank into her plush rear end, digging deeply into the squishy soft fat before meeting her strong muscles beneath.
“We shall try to ease thou into it this time.” she said in a hot breathy voice, looking down at you with lustful eyes.
Author's Note
I like to start off with a small quick read here before I add more. I don't care if this story sounds dumb, I want to write about growing giant pony asses.
You were lying down on a solid, cold-stone, yet invisible ‘floor’ within a white void. The room’s only distinctive feature was that there was a double golden door nearby on your left. Princess Luna was lying on top of you, she was merely four foot tall, and pretty lightweight at this reduced size.
Your hands were resting firmly on her buttcheeks, depressing her soft fat deeply from under your applied pressure. You could feel her strong muscles deep beneath her fat. Her soft, hooves were resting on your shoulders. Luna looked down at you with a warm smile. You, in turn, looked back up at her with a smile of your own.
Luna flashed her horn and simply made the hard floor beneath you feel like a soft, warm mattress, rather than stone.
“Thanks.” you simply said.
“Thou art welcome.” she said softly, leaning down to give you a simple kiss on the cheek, before pulling her head back up again.
The much larger form of Celestia stood nearby. She stood at least 15 feet tall or so. Her massive, elephant-like-sized body cast a dark shadow over you and Luna. She stood with her ass turned to you, giving you a perfect look at her huge, bubbly rump. The cheeks of her rump looked like supersized beach balls, they were perfectly round and smooth, and not saggy in the least, despite how big her cheeks were.
Without warning, Luna flashed her horn, causing your clothes to disappear.
You shuddered at the feel of the softness of Luna’s warm, silken fur against your skin. Luna raised her right hoof to her mouth and uttered a quiet giggle for a brief moment, before returning her hoof back onto your shoulder.
The mare pulled her ass back, positioning herself over your cock. You gasped upon contact with her hot sex.
You moaned softly as her marehood took your tip into her. However, you soon grunted in frustration when she abruptly pulled up. Your cock was now agonizingly close to her pussy, and was sandwiched between the soft cheeks of her ass.
“Hey! Come on!” you whined.
“No sex until we are given a proper apology.” she said in a mocking tone.
“What proper apology?”
“By being facesitted on by us.” she said lustfully, lighting up her horn with magic.
You looked up at Luna with sad eyes, a little upset that she still had not forgiven you completely.
“I’m sorry Luna.” you said softly.
“Relax. We promise that we shall give boring, vanilla sex at a reduced size later. But for now, we want to swell over thee, my little human.”
At first, nothing seemed to be happening. But then you looked carefully to see that Luna was rising by centimeters by the second. Your hands sank further into her plush ass as it augmented in size.
“Would you like us to grow faster?”
“Not at the moment Luna, this is nice.”
Luna sighed and gave you a sad puppy dog-like look.
"Luna, you can grow supernova speed later. I promise." you said softly, giving her cutie marks a tender rub.
Those loving words from you caused the mere four-foot tall mare to shoot upward in size to a five-foot mare. You gulped nervously, while Luna looked down at you with her eyes literally lit up with pink love hearts for a brief moment.
"Oh Anon, thy words are so romantic." she said in joy, with tears of joy falling down her cheeks.
Luna pressed her lips to yours and took you into a passionate kiss. Her large equine tongue entered your mouth and gently rubbed against your own far smaller, human tongue. While Luna wasn't being domineering, it became increasingly difficult for her to be gentle as she grew in size.
You and Luna moaned together as you kissed with passion as you rolled your hands over her rump, you squeezed and rubbed the soft flesh between your fingers, fondling it with love. The slowly expanding surface area of her rump only made it feel even greater to roam your hands over.
Her tongue took up more and more space in your mouth. Her long, thick tongue began to slither down your throat. You coughed, cut-off from oxygen as her massive tongue swissed back and forth down your throat.
Luna flashed her horn, teleporting herself back a little away from you. You could see Luna slowly rising above you now, as she looked down at you with dreamy eyes.
As she grew in size your penis became less and less adequate for her. Your hands began to sink further into her bloating rear end. Eventually, her rump became so thick that you could not reach her muscles anymore underneath.
You delivered a hard slap to her right buttcheek, which caused her to utter a throaty moan and her cheek to slap against the other one with a delightful sound of flesh slapping against flesh.
As she rose into the air your hands slipped further and further away from her ass. You leaned up, pressing your head against her soft, furry chest and tried with all your might to hold onto her growing ass. Luna giggled at this show of defiance.
“Our moons only grow bigger and more powerful by the second. Thou cannot hold out forever.” she said in a mocking tone.
“I can try!” you shouted.
Your hands pressed deeply into her soft, plush rear end. Despite the stronger hold you had on her ass, the sheer thickness of her rump was so great that you still could not reach her muscles anymore underneath the ever-increasing layers of soft fat from her growing rump.
You fought with all your might to hold onto her ass, but it was a losing battle. Your hands slowly, but surely slipped down her cheeks. Eventually, your hands landed on her thick thighs of her hind legs.
“Thou has fought valiantly, but to no avail. To stand against the power of alicorn butt, there can be no victory. However, we admire your futile resistance. We feel that thou should be rewarded for thy heroic last stand against the power of our rump later.” she said softly.
“What reward?”
“Thou shall find out later. But for now, watch as we grow over thee.”
You grunted struggling to hold onto her thighs, for they too were becoming increasingly difficult to hold onto. Eventually, your hands slipped away from her thighs to land between her legs. Your hands made contact with the great pillowy mounds of her teats.
You roamed your hands over her huge watermelon-like breasts for as long as you could, which made Luna moan softly.
You cried out in anguish as your hands slipped away from her breasts unto her waist. You made the best out of your situation and decided to give Luna belly rubs. This action made Luna utter a series of quiet horsey sounds.
Alas, your hands slipped further and further away from her, until eventually your hands now could simply touch her chest and neck for the most part.
Still, your hands could touch her front thighs and front hooves if you wanted to.
And that is exactly what you did. You placed your right hand on Luna's thick, right hoof, from there you gently rubbed her hoof back and forth. Luna blushed at this gesture, her growth coming to a stop.
"Careful Anon, these romantic gestures only encourage us to grow faster over thee. We are actively trying to keep our growth rate slow for thee."
“You don't appreciate them?” you said, pulling your hand away from her hoof.
Luna uttered a sad whine when she felt your loving hand no longer rubbing her hoof.
“Of course we do. It’s just that such things can cause growth triggers like what happened earlier.”
You simply nodded. Luna gave you a warm smile, before continuing her slow growth.
Luna was now the size of a full-blown draft horse at this point over you. She smiled down upon you, marveling at the size difference between you and her. You hissed in pain at the increasing weight of her body upon you, It was borderline badly painful but not too bad. In fact, it added spice to the feeling of Luna.
Abruptly Luna stood up. You were about to voice your protest before she slammed down upon you with her rump. You gasped as the wind was knocked out of you from the impact of her rump against you.
Her rump was now so large that it covered your entire head and most of your torso. Slowly her ass advanced downward to cover your legs until you were completely covered by her ass.
The heavily endowed mare pinned you down from under her enormous, meaty rump’s immense weight. Layer after layer of squishy soft fat smothered your entire body, the sheer thickness of her flanks were so dense they shrouded your entire vision in nothing but darkness. The soft fat of her huge backside folded around you like soft dough, depressing deeply around your small form. The heat from her marehood was amazing, which smelled faintly of blueberries.
A soft coo left the alicorn mare when she felt you move your hands slightly from under her oppressive weight. You used your limited mobility to place your hands against the soft fur of her backside, digging in deep into the thick layers of squishy soft fat. Though, it really wasn't that deep, since you could only dig into her ridiculously thick, soft flanks so far.
“Yes! Worship our divine rump, our little human!” she boomed.
You sighed in bliss as you felt your cock poke against her soft rear end, not bending in the slightest even with her enormous ass’s incredible weight upon it. The soft flesh of her ass folded around your cock as it pushed back her rump’s vast tide of fat. Your cock was poking against her cutie mark, this was a special place for ponies.
With magical aid, you were given a third-person perspective. Luna now was basically a draught horse at this point. Her rump was huge and bubbly, still maintaining its perfect, round smooth shape even as her cheeks looked like bloated beachballs.
Beneath the thick layers of fat, there was a super dense muscular structure. This helped her contain her perfectly model-like look. Ensuring that her rump would not be saggy in the least, despite the overwhelming thickness of fat her ass had as it air ballooned outward in size.
With loving passion, you squeezed and rubbed her soft fat between your fingers. From under your applied pressure, her plush rump conceded back like memory foam as you dug in deep into the thick layers of her squishy soft fat.
Experimentally, you pulled your right hand back and watched in delight the depression you left on Luna's cheek quickly fade away, returning to a perfectly smooth shape.
You placed your hand back down on her right buttcheek and dug into the soft flesh of her ass once again.
You leaned forward and began to gently kiss her soft, furry cheek, uttering muffled moans while doing so into her ass. You felt compelled to thrust your hips upward, in doing so causing your cock to grind against her cutie mark.
Luna abruptly uttered a grunt of frustration. This action caused you to stop grinding your cock against her cutie mark.
“Oh Anon, don’t stop.” she said softly. “We are not mad at thee. We are just finding it very hard to hold back our growth rate.”
With those reassuring words, you resumed grinding your cock against her cutie mark. To give her even more love you moved your hands over her cutie marks, circling around the edge of her crescent moons.
Luna uttered a loud, throaty moan at the feel of your loving attention toward her ass and cutie mark. This compelled her to begin bouncing her massive rump up and down over you. You continued to fondle Luna's ass with love as her heavy, meaty flesh slapped against your small body repeatedly.
Luna's growing ass was a blur of motion as she bounced up and down upon you without stop. However, for brief moments of time she would hold her ass down over you, allowing you to deliver her ass a gentle kiss, along with a loving rub and squeeze from your hands over her rump. She even gave you time to give her ass a few thrusts from your small (at least for her) cock against her rear.
Once satisfied, that you gave her ass enough love for the moment she pulled up before slamming down upon you again. The heavy softness of her rump bombarded your small body over and over again, her slams only becoming more and more powerful the bigger she got.
The huge, draught horse-sized alicorn mare sighed in bliss, closing her eyes as she grew and grew over you. The sounds of heavy, meaty slaps of her soft rump slamming against you, her throaty moans, and the intoxicating sweet blueberry smell of her marehood was driving you to your breaking point.
“.... I love you… Luna.” you said in a low voice as you became overwhelmed with pleasure, cumming on her ass, showering her with your creamy essence on a tiny area of her massive rump.
“I love you, too!” she boomed.
Luna’s eyes lit up with love hearts, and her cutie marks glowed with blinding light and her cheeks wobbled about like a stormy ocean. There came a low rumbling sound before she skyrocketed into the air.
Luna pulled her head back and unleashed the loud, throaty moan. Shockwaves exploded off her, sending Celestia far into the great beyond of the empty void as she grew into the air. The golden doors became far away into the distance as she rose into the size of a mountain over you. The mountain of which the city of Canterlot stood on.
The giantess mare above you giggled with a hoof over her mouth at her newfound size. The cheeks of her rump were like great cliffs and the gap between her cheeks was like a huge valley. You were at the bottom of this valley, smothered under her massive ass. Although not very noticeable, she was still growing, centimeter by centimeter by each passing second.
“Sorry Anon. We could not hold back growth any longer.”
“Mhhhmmmm!” came your muffled moan into her ass in approval.
