The afternoon sun hung over Ponyville, parting through the sparse clouds. The end of summer always meant a few mercifully cooler days as the Running of the Leaves approached. The ponies used the day to get those last few summer highlights in before the weather would cool, and their minds would turn to the autumn and winter ahead.

The mind of Princess Twilight Sparkle, though, was elsewhere. Sitting at the large writing desk in her room, she poured over letters, news articles, and research papers next to a small mountain of books. Yet another hour gone by of looking into the past history of her fellow princesses, and the ways that they’d used the ability to change size to their advantage.

Twilight couldn’t help but wiggle down deeper into her chair as she kept reading. Despite the window being open to let in some air, Twilight felt a little hot. All these articles, including papers from hundreds of years ago, about Celestia smothering cities under her breasts? It was hard to not get a little flustered.

All of the evidence was leading Twilight towards a more concrete theory. Alicorns were thought of as attractive beings not just for their looks or curves, but for the pheromones they gave off. At godly levels of power, there was no mortal species that could resist forever. And if growing made those pheromones stronger, mixed with the rapid increase in thaumetic power in the alicorn’s body…

It was no wonder that becoming a giant made everypony so helplessly horny.

“Mmmph. Focus…” Twilight repeated for the hundredth time, doing nothing to help. Twilight was focusing on her teacher, but little else. Imagery, descriptions, detailed accounts, even poetry about the gracious tits of the princess. City after city smothered under the white mounds of the sun goddess, pictures from every angle of every curve.

Then, the reports just within the last few days of Luna and Cadance. Every paper in Equus that Twilight knew of had reported on “massive flooding” in Canterlot one night caused by Princess Luna. A flood of equine cum unlike anything the world had seen before, all released in just a few minutes. They still weren’t completely done with the clean-up.

And every paper got to report a city-wide orgy in the Crystal Empire just the next day. Hundreds of photos of ponies slamming on every street corner, all while Cadance’s pussy rammed down on the castle. Many an article wondered when it was going to happen next. Just as many were looking forward to it.

It was practically becoming commonplace to see the princesses as giants!

“Oh, what am I saying?” Twilight said, standing up from her desk and starting to pace in a circle. “The princesses? Giants? Come on! That’s just silly! Sure, everypony knows about Princess Celestia smothering cities, of course! That’s normal! But then this thing with Luna, and that thing with Cadance, I mean, those had to be one-time things, right?”

Twilight’s pace circle quickened a bit.

“I mean, okay, I might be getting funny looks now, but when haven’t I? Ever since Princess Celestia made ME an alicorn, I’ve hardly been left alone out in public! Every day, somepony asking for my autograph, or wanting a picture, or giving me a couple dirty looks…

“Not that that’s really anything new, anyways!”

With a nervous laugh, Twilight’s hand slid across the fabric of her purple skirt, her ass getting a gentle tease. Then a not-so-gentle one a moment later. She blushed, even biting her lip. The thought of Celestia’s breasts descending towards her compelled her to make another squeeze.

Twilight did need something to ease all this tension. By the time she’d taken to reading softcore porn for her “research,” even she would admit that she was a little tense.

Part of that was where she was grabbing. Her ass. Her big purple ass.

Twilight’s booty had always been relatively big for a mare of her height. It was the one thing that made anypony make a pass at her when she was still just an ordinary unicorn. And while Twilight might have made the occasional objection, she still kept a variety of short skirts neatly stacked away in her closet.

When she had become an alicorn all that time ago, though, that’s when the eyes really went low. Her ascension from a mortal into a goddess had come with all sorts of changes. She’d gotten almost a foot taller. Her horn had gotten longer too, making her look like she’d gained even more height. The wings on her back were an obvious addition. Her modest breasts had gone from dull to at least decent, though nothing like the kind of perfection that were Celestia’s.

But that ass? Her hips had gotten wider just to accommodate it. The way it softly jiggled with every step she took, bouncing hypnotically underneath her skirts was impossible to ignore; Twilight just had learned to live with it. Thank goodness Rarity had been on hand to help adjusts her whole wardrobe after the ascension, too. Even if she had taken Twilight’s measurements a few too many times… “just to be sure.”

No doubt about it, Twilight’s little squeezes of her round rump and her sharp breaths were giving herself away. She had to relieve this so she could keep getting on with her work. With a soft glow of her horn, she closed the window and the door.

The only trouble was that there was nothing in the room that jumped out at her as a way to help relieve her stress. Twilight didn’t keep much in the way of the perverse in her bedroom. If any of her friends found it, she’d probably die from embarrassment. And if Pinkie Pie or Rainbow Dash found it, the whole town might get word of it. Better safe than sorry.

“Maybe it would be best to just get back to my notes,” Twilight thought as she slowly trotted back to her desk. As much as she tried to put the thought out of her mind, the wiggle of her hips down into her chair brought it right back.

That’s when Twilight noticed one of the pieces of parchment she’d left on her desk, one curled up in the corner. It was a letter that had arrived a few nights ago from Princess Celestia. The one containing two very notable spells. The spells she used to become the giant that everyone in Equestria loved.

Twilight took the scroll in her hands, looking over it a few times. She grasped the spells very quickly, student of magic that she was. Why else had Celestia sent her this, unless… She wanted Twilight to use it. She wanted Twilight to become a giant, like she’d been so many thousands of times before.

Twilight wiggled her hips down in her chair.

Now seemed like the perfect time for a quick test run.

Starlight Glimmer tugged at the collar of her jacket as she walked up the stairs towards Twilight’s bedroom. The things she had read from her sweet Sunburst’s letter had made her face turn a hundred different shades of red. Public sex, giant princesses, lewd displays of magic power… And that was just in the first half of the letter! That, and the things she read in the newspaper made Starlight have whole range of what she preferred to call “conflicting emotions.”

Even with the blush spreading across her face, Starlight still trudged towards the bedroom doors. Twilight was a princess, and had to know something about how it all worked. Starlight was particularly curious about it. If only for a brief flash of herself laying over her former sanctuary village, hundreds of citizens trapped as they helplessly tried to fight off her advancing spells… Making every last one of those traitors remember the name of…

Starlight quickly shook her head as she reached the double crystal doors.

Her hand tentatively grabbed the door handle until she heard a guttural moan from inside Twilight’s bedroom. Starlight paused, taking a moment before she leaned in, putting her ear to the door. There was silence, until another groan just a few seconds later.
Starlight knew she shouldn’t, but curiosity got the better of her. Very slowly, she opened the door just a crack and looked inside.

Her eyes instantly shot to the size of dinner plates.

Inside her room, Twilight was stark naked, reaching up to the thirty-foot ceiling, the curtains drawn and the lights out. What little light there was streamed through an open crack in the curtains, reflecting onto Twilight’s bare chest. Her hand was between her legs, the other rubbing one of her tits with a feverish passion.

Her eyes were closed. Her head was rolled back. Her voice was getting gradually louder, briefly echoing down the hallways. Twilight’s hooves were pushing down against the floor. Thin beads of sweat formed on her forehead.

Through it all, Starlight stood in the thinly-opened doorway, transfixed in a mixture of shock and fascination. The letter from Sunburst had already sent her mind racing; now, it was playing out in front of her. Starlight’s pulse quickened, and she felt herself breathe in sharply. It was only a quick but hard grab of the door handle that brought her back to reality. Spying on her teacher, masturbating as a giantess? Perhaps it was just better to retreat to her room with a little time for herself… with maybe a little time for a stop in the library for a few spell books.

Just as Starlight tried backing out, a loud screech pierced the air. Starlight jumped, darting her eyes towards the source of the scream, and found Twilight staring straight at her. In all of her eyes wandering, Starlight had forgotten to check if Twilight had actually noticed her. The two of them stayed perfectly still in awkward silence for what felt like hours.

Starlight was the first to speak up, brushing her hands over her clothes and trying to straighten herself up.

“T-Twilight! I’m so sorry! I didn’t mean to interrupt! I just got this letter from Sunburst, and I wanted to… I-I mean uh…” said Starlight, uselessly trying to untie the knots in her tongue as Twilight could only stare in embarrassment.

After a long clearing of her throat, Starlight began again, this time trying to keep her eyes off of Twilight. “There was this… letter from Sunburst, telling me what happened in the Crystal Empire… About Princess Cadance becoming a… a giantess…”

This time, Starlight couldn’t help but look at Twilight. She hadn’t noticed that her breathing was still getting heavier, and that she was standing with her legs gently crossed. The smell of sex hung over the air in Twilight’s bedroom. And even at only twenty-five feet, Starlight was entranced. Twilight could see Starlight fidgeting with her clothes in the doorway.

“A-And how the whole kingdom had turned into a massive fuckfest!” said Starlight, blushing as she suddenly heard herself use such coarse language around Twilight. “I-I mean… nngh, sorry, all of a sudden, it’s getting so hard to think…”

Twilight’s embarrassment had begun to fade once she saw Starlight’s rapid change in mood and behavior. The princesses had always inspired passion in their subjects, even before Celestia’s smotherings began. Twilight’s own theory about alicorns appeared to be playing out right before her eyes. But could it really be this strong?

Twilight simply had to know.

“Starlight?” Twilight said quietly, or as quietly as she could for being over three times her normal size. Starlight, for her part, kept blushing, grabbing the door handle and starting to pull it closed. She just had to go before this got any more awkward.

“Starlight!” Twilight said again, much more forcefully this time. Starlight stopped, the door now open just a crack, momentarily frozen in place.

“Starlight. I want you to come into my room.”

There was hesitation as Starlight opened the door again, slowly looking up to meet Twilight’s eyes. To emphasize her point, the torches slowly lit up, spreading light through the room. It was easy to see Twilight’s nude alicorn form on display now, and Starlight winced. She almost wanted to back out again, but she couldn’t, transfixed on her teacher’s body.

“Starlight…” Twilight said, their eyes meeting this time. “Take a deep breath, come into this room, and close the door behind you.”

Twilight’s horn wasn’t glowing. There was no magical manipulation. Even so, Starlight felt compelled to do as she was told, slowly stepping into the room with a deep breath, closing the door with telekinesis. She never took her eyes away from Twilight’s. Her breathing was growing into deep draws of air, the smell of sex stronger than ever.

Twilight pulled her hand away from her chest, rubbing a small section of the floor between her legs. “Come here, Starlight.”

There was still the odd hesitation or moment of doubt, but nothing that told Twilight that Starlight wouldn’t listen. Starlight stopped between Twilight’s legs, biting her lip and quivering. Her arousal was gradually becoming even more obvious, tugging at the collar of her jacket, her eyes on Twilight’s pussy. Her breaths were taken in sharp bursts, drawing in the smell of the heated air around her.

“Twilight… please…” said Starlight. The way her eyes were fluttering made it hard to tell if she was trying to fight it, or wanting more.

Twilight felt her face flush ever so slightly. She had to say a few silent praises to Celestia and Luna. It must be so tempting to use this kind of power on somepony else, one they’d have felt for far longer. They must have even more remarkable restraint than Twilight thought.

“Starlight.” Twilight sat up as straight as the ceiling would allow, her long horn tapping against the crystals. “Take off your panties.”

Starlight’s eyes snapped up to Twilight’s. Even so, her horn was already glowing, her legs bunched together.

“With your hands,” Twilight said with authority.

“B-But… I…” Starlight muttered, trailing off into a whisper while her fingertips slid beneath her skirt, slowly pulling down a set of white panties past her hooves and onto the floor. Her panties were followed closely by her skirt, then her jacket, her shirt, her bra, and everything else she had on, one piece of clothing at a time, until she was stripped naked.

Starlight didn’t even feel embarrassed anymore. By the time she’s stripped herself down, her hand was rubbing between her legs, walking ever closer between Twilight’s.

“Starlight?” Twilight said in a low voice. Starlight didn’t answer. Instead, she could only reach up and start rubbing over Twilight’s folds, twirling her tongue around the large clit before her. The taste of Twilight instantly flooded into her mouth from the damp folds before her, only prompting Starlight to start swirling her tongue quickly.

“S-Star…! NNGH! Starlight!” said Twilight with a gasp as her wet pussy instantly began to leak its juice across Starlight’s smaller body. The smell that had made Starlight so helplessly horny stuck to her coat as Twilight drenched her, her grip tightening and her breathing growing heavy.

“T-This, this is… oh goddess, I need you so bad!” Starlight shouted from below as she was slicked up by the juice. Her mane matted down, her coat sticking to her skin, all she could do was lick and rub, savoring the taste of Twilight’s sweetness. As she lost herself to her maddened lust, suddenly Sunburst’s letter began to make sense. She wanted to lick, and never stop licking.

Twilight pushed her hands against the wall. She hadn’t counted on how sensitive she would be at this size. The Harmless spell was all that was keeping her from breaking the walls apart with her earth pony strength. Starlight’s tongue felt divine. Every lick sent a shot of pleasure through every nerve in Twilight’s huge body. Even the tiny rubs of Starlight’s hands felt good enough to make Twilight want to scream to the heavens. Her legs began to close in around Starlight, a mountain of soft purple skin surrounding Starlight on all sides.

As the heat from Twilight’s pussy grew hotter, Starlight’s horn glowed, sending a small beam of pleasure directly into Twilight’s drenched folds. Instantly, Twilight shouted her approval, rocking her fat ass back against the wall with a rumble. The beam came again, to another sinful shout of incredible lust.

Starlight panted. What she was about to do might have been crazy. But that didn’t matter. All that mattered now was pleasing Twilight. Her horn gave off a bright teal glow before unleashing her magic in a constant beam, blasting Twilight’s pussy with its blissful power.

Twilight screamed.

Her honey flooded from her pussy in large waves over Starlight. Twilight’s fists slammed into the walls, lost in divine release. Starlight was soaked in the tide, the taste and the smell of sex permeating the room. She never stopped licking, never stopped rubbing, never stopped her magical bliss for Twilight.

The room was quickly flooded. Twilight’s flow covered the tile floor in honey, leaking under the door and spilling down the stairs. The flow in her room gradually rose as the orgasm continued endlessly, everything it touch growing damp with Twilight’s scent. The power of the alicorn’s musk overwhelmed Starlight, driven into maddened passion by it all, helplessly humping herself against the drenching folds. Starlight’s own pussy was convulsing in orgasm, every cry of lust filling her mouth met with more honey for her to swallow.

Twilight’s horn began to glow. This was bliss. But it could be better. She wanted more. Pumping her magic into her body, Twilight hunched over as she filled the room, the pleasure from Starlight’s beam keeping her release constant.

As she became cramped inside of the room, Twilight managed to open one of her eyes to see her student faithfully licking, rubbing and zapping between her legs, the alicorn lust overtaking her. Twilight wasn’t done, but there was nowhere else to go.

Unless…

Outside.

“S-Starlight!” Twilight said through sharp breaths. “I-I can’t…! UNNNH! I have t-to get outside!”

As Twilight’s horn glowed, one last powerful wave of juice knocked Starlight off of her hooves onto the floor with a splash. And in an instant, Twilight vanished. A faint flash from the teleport burst was all that was left to accompany Starlight.

“N-No! Don’t… aaaah… d-don’t go…!”

Starlight’s hand dove between her legs, rubbing hard. Even with Twilight gone, the smell of the divine orgasm was everywhere. Starlight could only rub for dear life. Her other hand clasped a huge tit, playing with her nipple. Her tongue hung from her mouth as she panted. Every inhale drove the lust on.

Starlight’s pussy quivered again as her own tiny squirts of juice were added to the flood. Her hand didn’t relent. Her fingers pounded deep inside of her folds. She laid half-submerged in the lake of Twilight’s honey. She didn’t stop. She couldn’t stop.

She never wanted to stop.

Ponyville Public Park always had its fair share of visitors in the afternoon. Especially now, as ponies gathered to watch the leaves turn brown, and felt the warm summer heat give way to cool, gentle breezes.

For Rainbow Dash, this was the perfect weather for napping. Her hands rested lazily behind her head as she floated high above the park on a fluffy white cloud. Her eyelids felt heavy as she drifted in and out of consciousness, a smile curled across her face. Rainbow never needed much of an excuse to take it easy, but a clear schedule meant that all those lost hours of napping could finally be made up for.

Just as Rainbow’s eyes closed again, there was a sudden loud burst that rang across the town, followed by a few startled creams. Rainbow’s eyes shot open, frantically darting to her hooves on the cloud.

“What in Tartarus was that!?” She checked the skies for any signs of things fired from a party cannon. No fireworks, confetti streams or poppers in sight; this wasn’t the work of Pinkie Pie.

And then Rainbow looked down.

Twilight gasped, still clutching between her legs as she appeared outside in the open space. With Starlight’s licking finally gone, she began to slowly catch her breath, even as the ponies all around her gasped. The sight of Twilight lewdly clutching herself drew the eyes of everypony in the park to her. It hadn’t occurred to Twilight in her desperation that she’d be spreading these alicorn pheromones across anyone who got close. The little bit of juice she’d already leaked onto her palms was enough to catch everypony in quite a ways from her.

And that included above her. As Rainbow stared down from her perch in the clouds, her embarrassment turned to curiosity, flying down in front of Twilight’s chest.

“Er, Twilight? You, uh, wanna tell me what’s going on?” said Rainbow, gently beating her wings, sending a breeze that slightly cooled Twilight off. She opened her eyes to see Rainbow, taking in deep breaths and exhaling slowly. The ponies beneath her had begun a slow approach, a crowd starting to form.

Twilight looked down at them all. From where she was sitting, they all looked so tiny. But she knew, thanks to the Harmless spell, that she couldn’t hurt them. She’d pushed against the walls of her castle in unrestrained lust. They’d be alright if she…

“Ummm… Twilight? You there? What’s going on?” Rainbow said, louder than before.

Finally, Twilight looked down at Rainbow. Twilight’s eyes were half-lidded, pushing her big purple ass against the cool grass underneath her.

“I need more.”

Rainbow’s brow shot up. “More what?”

“More!” Twilight shouted, her horn suddenly pulsing with magic. “I need more! More! MORE!”

Twilight grew as the Size Shift spell shot through her body. Before Rainbow could even shout her objections, Twilight’s chest had already pushed against her, sending Rainbow clutching onto Twilight’s chest as she kept increasing in size. Down below, her booty grew across the grass, her legs spreading out further. The trees swayed and bent from the power of the Harmless spell as Twilight poured more power into her horn.

“Nnnngh! T-Twi… light!” Rainbow said while trying to break free of Twilight’s body, drawing in heavy breaths as she pushed and struggled. She was far from the only one, as several ponies were smothered beneath the growing ass of Twilight, stuck underneath huge, growing mounds of softness. In just those mere moments, Twilight had outgrown Town Hall, and was still getting bigger.

The sight of Twilight growing larger, along with her moaning and grunting, was impossible to ignore. Most of the initial reaction wasn’t panic, but confusion. They had known Princess Celestia to smother their town, but Twilight? Nopony was quite sure what to make of this literally growing problem… Until they saw Twilight’s fingertips push between her legs. The scent washed over them in an instant as the beautiful alicorn drew closer and closer to town.

Twilight could have theorized about how she was driving everypony mad with lust, but her mind was more clouded than anypony’s. Her huge soft ass had grown over the row of homes and shops around the town. At this size, her pussy was leaking continuously, the flow increasing as she kept getting bigger. Even a moment of her orgasms would be enough to flood a single house down below. Her screams of lust could be heard as far away as Cloudsdale. The ponies trapped underneath her had taken to grabbing onto Twilight’s softness, licking and trying to pleasure her as much as their bodies would allow.

Somewhere in the back of Twilight’s mind, she knew how indecent this was. Writhing, moaning and growing, rubbing herself off in public for everyone to see with her ass sliding across their homes? And just as quickly as those concerns popped up, her volcanic lust shot them down and buried them deep inside her mind.

The town of Ponyville wasn’t far behind her. In their home, Bon Bon had grabbed Lyra’s top and literally ripped it off of her, while Lyra had blasted away Bon Bon’s dress. The two lovers grasped and sloppily kissed on their bed, all pretense of lovemaking dropped. They wanted each other with maddened passions, and nothing was going to stop them.

Twilight still wanted more.

“Everypony… hold oooonnnnnNNNNNGH!!”

Twilight’s horn glowed bright enough to light up the afternoon sky as she rocketed up in height. The maroon light blanketed the town for a few moments before Twilight’s booty did, her explosive growth rendering her close to the size of Celestia the last time she’d smothered Ponyville.

Twilight was in Heaven.

Celestia stood on her balcony, an amused smirk curled across her face.

“We are glad you find this so amusing!” said Luna, pouting at Celestia as she buttoned her pajamas. “Tis the middle of the afternoon, Tia, and you wake us up to see Twilight Sparkle growing out of control?!”

“Oh, Lulu, must you always be such a stick in the mud? It’s only my faithful student trying to follow in my hoofsteps.”

“That is hardly what we would call this debauchery, Tia! The way she’s growing, she might not stop until… Well… She might just get TOO big!”

“First of all, my dear sister, there is no such thing as ‘too big’ for a princess,” said Celestia, the purple dot on the horizon gradually getting larger. “Second, Twilight is responsible. Look; see how Ponyville’s intact? She’s already cast Harmless on herself, just like she was supposed to.”

Celestia smirked. “Besides… If you’re so concerned about damage, what was that flood all about?”

Luna’s cheeks turned a burning shade of red, unable to counter that.

“Still…” said Celestia, who had turned her eyes up to the clouds, “I think I have an idea of how to get her back on track. Try not to stain the walls in your room while I’m gone!”

Luna opened her mouth to scold her sister, but Celestia was already gone with a golden burst of teleportation. Luna scoffed, looking down from the balcony again, trying to ignore the throbbing beneath her dress that was getting stronger.

Twilight had collapsed onto her back, jolts of pleasure shooting through her nerves constantly. Her pussy alone was enough to swallow the entire town of Ponyville twice over, covering it in a torrent of her honey. Her right hand feverishly worked between her folds, her left hand squeezing a breast that was bigger than ten of her castles. All the while, her horn pulsed with incredible magic, making her grow in constant bursts, each one adding more size than the last one.

“Nnnnngh! G-Gonna… UNNNH!” Twilight grunted, feeling her town gradually rubbing across her ass. A few more pulses of size, and she couldn’t even notice it anymore.

The rest of Equus had begun to notice Twilight’s ascension as well. Some of the planet could see her coming towards them on the horizon, and more of it could hear her moans echoing through the air.

Twilight’s eyes were shut tight. She didn’t need to see how big she was anymore. She could feel it. Every moment she grew bigger, she could hear someone else moaning and grunting, calling out her name. Her lips curled into a perverse smile.

A single word echoed across the planet.

“More.”

Twilight’s hands slammed down onto the surface of the continent below her, starting to sit up. Her horn was glowing as bright as Celestia’s sun, pumping more and more magic through her body. She cast and recast the Size Shift and Harmless spells constantly, sending a delightful tingle down her back that kept her wings uncurled. Even without orgasm, her pussy was leaking a flood of her juice, covering the measly continent below her. The vast empire that was her purple booty spread across the land, covering anything it touched in a thick, soft pillow of divine flesh.

“More!”

Twilight felt her hooves splash into the ocean on the western side of Equestria, her hands behind her entering the eastern ocean. She was as big as the entire continent.

Much of it had already been overtaken by the insane lust that currently gripped Ponyville. In Manehattan, as Twilight’s butt filled the horizon, Suri Polomare was bent over the table of a coffee shop, her skirt yanked down to her hooves, scratching across the table and grunting. The pony ramming her tight ass, Java Bean, panted as she stared out the window at the growing show that was Princess Twilight, Java Bean’s hard cock twitching and swelling inside of Suri’s ass.

In Griffonstone, Gilda dug her talons deep into the earth as she was rammed into the ground from behind, her ass squeezed by a particularly cute male griffon. Her wings flapped as another griffon landed in front of her, desperate to find a hole on someone that wasn’t taken. He stuffed his cock into Gilda’s beak without a word, who happily obliged him, grabbing his legs and sucking down his shaft.

Dragon Lord Ember’s hands gripped two draconic dicks, jerking them furiously as her pussy and her ass were both slammed by two more. Her mouth was stuffed with a dragon cock almost as big as her arm, yet she still fervently gulped and licked across the tip. Several of her bigger subjects had taken to rutting each other, the former lord Torch threatening to cover all of them with a volcanic eruption of cum at any moment. He had already leaked enough lakes of seed while holding back his loads to cover the mountains in it. The other dragons all licking his balls with their tongues and the flames was only making them bigger. They had to hurry; that massive wall of purple was growing ever closer, and would be here any moment…

Twilight loved it. Everything about it. Driving everyone into this massive fuckfest. The burning heat in her pussy. The lakes of her glorious juice that flowed into the oceans of Equus. The smothering of her home continent beneath her titanic ass. Now they knew. They all knew how perfect her booty was. Not even Celestia came close.

“MOOOOORE!”

Twilight’s hands raised into the sky, a blinding flash of maroon light covering the planet. An instant later, her booty had spread across the oceans to the Dragonlands. Even the craggy mountains and the hundreds of huge dragons could do nothing to stop the advance of her ass, covering all of them. The mighty dragon Torch couldn’t make so much as an itch in her softness, grabbing on with his claws and humping is way into bliss.

Soon, Twilight saw the clouds parting and the sky growing darker. The starry expanse of space drew close as she felt herself beginning to drift off the planet, her tremendous weight now greater than that of her home. Slowly, Twilight felt herself pull away from Equus, leaving the ground with a low rumble in the planet’s core. Her magnificent moon of a booty slid away from its prize as she drifted away, her nethers still leaking thousands upon thousands of gallons of her cum. At her size, she barely felt it.

What she could feel was her fingers pounding into her tight pussy. Over and over, she worked herself faster and harder than she thought possible at this size. She opened her eyes for just a moment. There it was. Space. She was bigger than a planet. And she still wasn’t stopping.
She was growing so fast that her ass moved back towards Equus. Her smooth rump curled its silky soft cheeks against the planet as she grew. The ocean’s waves rocked against her ass. A gentle squeeze sent vibrations through every land mass.

The towns of the world had devolved into massive orgies. Every mare and colt that wasn’t slamming one another was grabbing the immense purple ass as it rolled back over their planet. Even Luna had taken to mindlessly humping. Her cock was gushing a load even greater than the night Celestia had grown. Cadance was desperately slamming herself down onto her husband’s throbbing cock. They didn’t speak beyond grunts and moans, staring into each other’s eyes.

It was the first time since her ascension that Twilight really understood what it meant to be a goddess. She had never felt more powerful. She had never felt more sexy. She wasn’t even embarrassed anymore. No, she wanted everypony to look at her. Not just look at her, but worship her. For everypony wanted to know just how good this felt. She wanted everyone down on their knees and begging her for the pleasure, the honor, the privilege of seeing that enormous mound of an ass.

Twilight’s last release finally came. Oceans of her honey flowed into the depths of space, her head tilted back, screaming. She grabbed a tit as large as Equestria itself, her entire body on fire with orgasmic bliss. As her juices spilled back across the heavens, the planet was smothered in softness from Twilight's rippling ass.

Twilight couldn't even remember when she'd started cumming, or for how long, as her nerves finally relented and allowed her to rest. All she knew was that she'd gone from the size of her castle to outgrowing Equus itself. She opened her eyes again, adjusting to the darkness, still panting and catching her breath. A sharp few inhales made Twilight’s sharp mind finally turn back on, suddenly confused.

“Wait a moment,” said Twilight to the void. “I’m in space. Ponies can’t breathe in space! How could I be catching my breath, let alone breathing at all?”

“An astute observation as always, Twilight,” said a sultry voice from behind her.

Twilight recognized the voice instantly. A lump formed in her throat as she slowly turned her head to see. And when she saw her, Twilight’s eyes went wider than Luna’s moon.

Celestia’s continental smirk betrayed her as her hands rested on her waist. As huge as Twilight had grown, Celestia was far bigger, with Twilight floating between her hips and the bottom of her enormous breasts. Celestia’s sun shining far in the distance almost made her glow as the star’s light hit her pure white coat.

“Ah! P-Princess!” Twilight stammered, her face turning a bright red as she tried to cover her chest and her crotch with her hands. “I was… uh, I was only…”

Celestia’s arms crossed over her titanic tits. “Smothering a planet?”

Twilight’s face turned a brighter red, only now realizing that the planet was still resting against her ass. She quickly pulled herself away, letting it get back onto its orbit and releasing the lustful grip on the world.

“Sorry!” said Twilight. “I don’t know what came over me! I just started casting those spells, and this… urge came over me unlike anything I’d ever felt before! I wanted to grow, and grow, and never stop! I’m sorry, Princess!”

Celestia chuckled to herself, her right hand gently clasping Twilight and bringing her close to chest level. “Oh, you have nothing to apologize for. Believe me, Twilight, I understand. That’s what it felt like to me the first time I grew. I must admit, I’ve always wanted to see what kind of limit there was on these spells. Now I know there’s no such thing, thanks to you. Well done… Princess.”

Celestia’s thumb started kneading itself into the softness of Twilight’s booty, making the student stifle a moan, biting her lips. The blush across Twilight’s face stayed just as hot.

“As for breathing in space? That was me applying a little safety net while you were distracted. I didn’t want to interrupt your fun, so I had to cast the spell without you noticing,” said Celestia, bringing Twilight in close to her chest.

“P-Princess Celestia… I…” said Twilight quietly as her hands reached out to the huge white breasts before her, kneading her palms against the jiggling beauty.

“Shhh… Just relax, my dear. You’ve had quite a day.”

Twilight slowly nodded her head against the canyon-like cleavage in Celestia’s boobs, still gently kneading the beautiful tits in her hands. Twilight’s eyes drifted closed, only the occasional soft moan escaping. Celestia’s smile went wider, looking from Twilight to their small home planet, then out to the stars that surrounded them.

An infinite plane, full of an infinite number of planets and stars, with infinite room to grow.

The smile on her face was almost as bright as the sun itself.

Author's Note

And that's all for this version. At least Celestia's getting a few ideas.