Today the sun was high in the sky, birds were singing and all that stuff in the somewhat medieval looking town known as Ponyville. The place looked medieval, but it was far cleaner than the average medieval town and it had many modern appliances like toilets, electricity and running water.
It was too sunny today for you. Nestled within a huge ass oak tree, you lay upon a purple couch in the middle of a dusty old library. Held in one hand you had a book, with lots of pictures of big ass horse butts… not too fat though. You merely wore a pair of white shorts and nothing else, which did little to hide the big tent you made from seeing such fine horse butts in the book.
Peace and quiet you had here, but you held off from masturbating. This was a public library after all. Unfortunately, your peace was soon broken by the sound of approaching hooves.
“Anon?” came a soft, feminine voice.
You lowered the book to see an all too familiar four foot tall yellow pegasus before you.
“Yes, Fluttershy?” you replied softly.
“Well… Anon… I... well… I was…. wondering if we could...” as she spoke, her body steadily rose by an inch a second, like a slowly inflating balloon her body grew larger, her rump in particular received a strong augmentation of growth.
“Oh my.” she said, bringing a hoof to her mouth and blushing profusely as the growth flowed through her.
You sighed deeply. “Sorry Fluttershy. I'm not like the stallions of your world, I don’t like crawling inside a growing mare’s pussy.”
“Oh… okay.” she said in a low voice, her growth coming to an immediate halt… and causing her to shrink back down to her normal four foot size.
“Don’t get me wrong, I would screw you, but the whole growth thing ruins it for me.”
“I… I… understand. Thanks for letting me down easy.”
With that Fluttershy walked away, her hooves quietly clopping upon the wooden floor.
You sighed, turning your gaze to look back at your book.
Your peace however was short lived.
“Anon?” came a new soft, feminine voice.
You turned your head to the side to see Princess Twilight Sparkle, sitting on her rump before you, giving you a pleading doggy eye look.
“Can I have a belly rub?”
“Will you grow during this belly rub?”
“Nope. I figured out a spell to stop my growth.”
“In that case then, of course you can Twilight.”
She clapped her hooves together, while making a sound like a dog’s chew toy in joy.
Twilight climbed onto the couch, and snuggled up to you, pressing her plump, soft rump against your crotch. You loved the feeling of your rock hard member poking against her, a nasty grin was on your face.
You reached your arm around her, and placed it upon her tummy, the mare shivering at your tender touch. Once your hand was in place you began to gently move your hand back and forth over her soft fur.
Soft coos and moans left her as you rubbed her belly, and there was no growth on her body in sight. However, she seemed to be sweating profusely for some reason, and her horn was sparking.
“Twilight, are you okay?” you said in a concerned tone.
“Um….. I’m really struggling to hold back the growth. Your belly rubs is causing my growth magic to activate.” she said in a nervous tone.
“Oh no.” you said in a low voice.
There came a low rumbling as Twilight’s whole body began to wobble like jello.
“I’m sorry Anon!” she screamed, before exploding outward in growth, an avalanche of soft fat from her rump instantaneously smothering you.
Rather than just see darkness underneath her rump, her magic allowed you to see her growing in real time.
Her rump’s cheeks exploded outward towards the walls, bulldozing them down like nothing, once outside the confines of the library she rose like a mountain in the town. Surprisingly, the inhabitants of the town were not panicked in the least, allowing Twilight's ballooning cheeks of her rump to roll over them. The ponies were not destroyed underneath her, in fact they thoroughly enjoyed themselves, by humping themselves against her squishy soft rear. They payed great homage to her mighty alicorn rump by the addition of licks, kisses and rubs.
Twilight grew and grew, her rump quickly bulldozing down the entire town, smothering everyone in her expanding thickness of her mega ballooning cheeks.
A great mighty canyon formed between her massive cheeks, two gaping holes that were her asshole and vagina became so large, they were like giants dark pits of of abyss, only becoming darker and deeper as she grew ever larger.
You squirmed beneath her as her weight rapidly increased, it felt slightly painful to be under her colossal rump, you could only feel the pressure increase as she piled on the weight. You could not help get an erection nonetheless, and despite the overwhelming weight of her rump pressing down on your member it did not bend in the slightest.
You were glad that there was some degree of protection magic, otherwise you'd be little more than bloody jelly at this point. And also you still maintained the ability to breathe.
Twilight moaned aloud at the feeling of the growth flowing through her, topped off with the tender touch of ponies below giving her growing rump a massage, their hooves deeply compressing the squishy soft fat. The stallions of the local area reported for duty, their cocks raising to attention for their princess.
Twilight closed her eyes, her tongue lolling out of her mouth as her marehood flowed like a river, flooding the surrounding countryside with her creamy essence. Through her monstrous growth, the cheeks of her massive rump jiggled like crazy as more and more mass was pumped into them. The growth was at its strongest in her rump, each cheek alone was already the size of Mount Everest, and still growing, faster and faster.
Fatter and fatter, heavier and heavier she became. Her rump’s weight soon increased to such an extent it began to dig into the earth itself, creating a deep crater. Those beneath her were not harmed in the slightest. At the same time, her colossal, ballooning flanks came like tidal waves over the land, flattening mountains under trillions of tons worth of alicorn booty flesh.
Twilight rose up into the clouds, her massive rump rolling across the countryside, destroying infrastructure and the landscape around her, but otherwise not harming any living thing in her path. And her growth was accelerating with each new pony worshiping her rump as she expanded.
Stallions from all across the land humped against her massive butt with wild abandonment, each ejaculation they released caused a violent surge of growth to the giant alicorn above them. More and more towns and villages were smothered under her as she expanded.
When Twilight's rump reached Canterlot, the densely populated area of new worshippers caused her growth to accelerate greater than ever before.
Like an exploding nuclear bomb, her rump expanded across the surface of the planet. In mere seconds Twilight’s head rose out into space itself, the entire continent of Equestria disappearing under her rump, and the entire population of said continent was content in helping her grow even larger at a faster rate, by giving her rump some well deserved worship.
Through this growth spurt her marehood violently unleashed a massive surge of her creamy essence, flooding the entire planet with oceans of her creamy goodness. Gigantic tidal waves rolled across the planet, drowning all in her love cream. Those trapped under her love cream still maintain the ability to breathe. The smell of sweet blueberry was in the air.
The weight of her body was now so intense that the entire planet was split in half. Nonetheless, despite everything that happened, the growth magic protected all living things around her, and didn't cause any mass extinction events. You were thankful that these ponies had some safeguarding magic to protect those around them from their terrible growth magic.
Stallion cocks rose to attention from all across Equestria, ready to worship the Princess of Friendship, so she can grow even bigger at a faster rate.
“Muuuummmmauuuuaaa!” you growled with a mouthful of big fat horse ass in your mouth.
Twilight sighed sadly, the rejection of her special somepony… or special somehuman in this case made her growth rapidly begin to reverse, the oceans of marecum drying up. While she receded in size, the damage she did to infrastructure and the planet quickly repaired itself. Further and further she shrank, until she was about four foot once again.
Millions of voices cried out in anger over you stopping her growth.
The two of you were now back in the repaired library. Twilight was on your chest.
You were about to vent your anger at her, but the sight of her heart broken look instantly stopped you. The tears streaming down her face from her badly bloodshot eyes looking up at you melted your heart.
“I’m…. I’m… sorry Anon. I couldn't hold the growth back, it was just too strong.” she said in a low voice.
“It was a start Twilight, I’m sure one day you’ll be able to hold back the growth.”
“I’m not sure If I can… Alicorns grow much faster than the average mare. The growth you saw there is actually slow when compared to Princess Celestia's level of growth.”
You shuddered, remembering Princess Celestia’s terrifying growth of omnipotent scale.
“You must do research!” you bellowed.
She gave you a solute. “You’re right, Anon. I’ll try find a more powerful spell to hold back the growth, then we can have sex.”
“Why ya even bother?!” came a strong southern accent.
Twilight gasped in shock, turning around to see Applejack, wearing her usual stetson hat.
“How could you say that!?!” she shouted.
“Twilight, don’t make a fool out of yerself. If Anon was a good little stallion, he’d love ya no matter what size ya grew to be!”
“I-I… well… uhhhhhhh…. You shut up.” came your amazing comeback.
“Maybe I want to feel a stallion fill me up for once, without my butt growing too large for him to fit.” Twilight shouted.
“Heresy!” Applejack bellowed, pointing a hoof at her. “A pony’s butt can never be big enough!”
“Well Applejack, I’ve grown quite keen on the idea of having sex with someone, without the need of them going inside my vagina for once.”
“Heresy! I can’t stand this heresy!” she shouted.
With that Applejack trotted off, shouting ‘Heresy!” over and over again.
“Is she insane?” you inquired.
“No, she's just a hardcore traditionalist, who firmly believes a mare’s butt can never be big enough.”
“Why exactly do ponies grow bigger?”
“Only mares grow bigger. Generally a more attractive mare is, the stronger her growth will be.”
“I have a feeling I am in some sort of weird fetish universe.“ you said in a worried tone.
To Be Continued
