Author's Note

Hello again, everyone!

This is an alternate universe oneshot set in the Mad Cupcake universe (link: here). So you might want to go and read that so you get a better sense of what is going on here.

Contains weight gain, entropy, lots of cupcakes, and Celestia and Luna getting alarmingly fat.

A Mad Cupcake World was originally commissioned by fatblack.

And this oneshot was commissioned by Untaken!

A Mad Cupcake World: Canterlot

Princess Celestia relaxed into her throne with a soft huff, watching as Twilight slipped through the large double doors at the opposite end of the throne room.

“With Twilight being so keen to leave early, we must have succeeded.” Luna remarked from her throne.

Celestia nodded, “That is true. With how well the peace talks went, I was worried she might try to stay for longer to continue to impart friendship onto the delegates.”

“That’s probably for us to do, now.” Luna sighed. “It was good to see her, and better still to have her help. If she’d been around at the dawning of Equestria, things would have been much simpler for us.”

Celestia nodded again, hard to argue that. Especially considering that Luna had a point. “She’ll be excited to return to Ponyville. I know how much she missed her friends. Besides, I think we can handle things from here on out.”

“As if we really needed the help.” Luna’s voice was light and teasing. “You have a thousand years experience, and it is not as if I’m inexperienced either.”

Celestia chuckled, “Alright, alright...Well, you know I won’t always be around to help her. Or she may find herself in situations where I can’t be reached. I’m still her teacher, even if we are closer as equals-”

There was a pop! And Celestia was cut off by the appearance of a dozen boxes appearing in front of her and Luna. All branded with the familiar symbol of Sugarcube Corner.

“Oh!” Celestia licked her lips reflexively, always willing to devour a few sweet treats. “What a nice surprise! Didn’t Twilight say that Discord was helping Pinkie?”

“Can we trust these then?” Luna asked, sitting up more fully and eyeing them suspiciously. She’d always been less trusting than Celestia had been.

Celestia leaned in, sniffing cautiously as she used her magic to open one of the boxes. “They’re cupcakes, Sugarcube Corner’s specialty! They’ll be fine, perhaps he’s just proud of his work and wants us to see his progress.”

Luna rolled her eyes, but acquiesced. Opening the nearest box to her and taking a cupcake.

The two princesses took a bite near simultaneously, and unknowingly changed the fate of Equestria for years to come.
The cupcakes were everything cupcakes should be. Light, fluffy, chewy, moist, with enough icing to make it creamy without overpowering the cake. The Cakes, and Pinkie, were honestly some of the best bakers that Celestia had had the pleasure of knowing.

She didn’t notice as the magical effects of the cupcakes took hold, and neither did Luna. Both so wrapped up in a sudden, inexplicable hunger that tore at their insides and drove them into eating box after box of the delicious treats.

New memories began to take hold as they continued to binge. These weren’t just cupcakes sent as a rare treat, oh no. It was Equestria’s worst-kept secret that the royal sisters shared a sweet tooth like nothing else. So it was customary for ponies to send them treats all the time, as a form of gratitude for all their hard years of service and work.

Celestia had been grief-stricken at the fall of the Everfree City and Luna’s banishment, and this tradition had helped her cope with her sister’s absence. Luna, once she’d returned, had been quick to adopt the practise. Hoping to cut down on the amount of sweets Celestia could demolish in one sitting, but she’d quickly grown to love the practice.

They were both quickly growing too. The magic altering the palace, the staff, and the throne room as the two mares gorged themselves. The dias their thrones rested on grew bigger, the thrones too. The kitchens tripled in size, the amount of bakeries and cafes in Canterlot boomed.

All the while, Celestia and Luna’s bodies grew. Celestia was obviously heavier, from her near thousand years of gorging, but Luna was certainly more than pudgy in her own right.

It was only because Celestia was fighting to open the next box of cupcakes that she noticed when Discord and Twilight popped into the room. Slim, trim Princess Twilight Sparkle looked worried and unsure, but Discord seemed to be explaining something to her. His wide, flabby body jiggling and wiggling as he gestured around.

Then the box popped open, and they were gone. And Celestia’s attention was consumed by the sugary treats once more.

(LINE BREAK)

Somepony was trying to speak with her, but Luna ignored it in favour of pushing another chocolatey cupcake into her mouth to chew it languidly. Her front legs hung limply from her flabby body, spread wide to make room for her doughy pigeon chest.

“Please, Princess Luna, you have to stop eating for a little while! Wouldn’t you like to rest your stomach for a while before dinner? I can make whatever you want-” Sea Shores, one of the palace’s chefs, was cut off when Luna grabbed another cupcake to eat before she’d completely finished the one before it.

Marjoram and Carnation were trying to gain Celestia’s attention, with no better luck.

Both princesses were massive. Immobilized, they had been moved to opposite sides of the throne room by Discord’s magic. Their altered memories said they had been moved apart sometime last year after Celestia’s rear had almost crushed Luna’s. It was just safer. They faced each other, their rears facing the beautiful stained glass windows that Canterlot was known for.

“Why isn’t she doing anything?” Carnation asked, pushing a hoof into Celestia’s chest, jumping back when Celestia visibly gained weight after downing another cupcake.

Carnation was tall and broad. Her honey-brown coat and dark brown mane and tail spoke of her strong Earth Pony heritage. Even though her twin’s golden coat and white mane and tail spoke of the Unicorn blood that ran through them both.

With several flaps of her wings, Shores worked to hover in front of Luna. Waving her hooves in front of the princess’s face in the hopes of catching her attention. “Princess, please!”

Nothing but the sound of chewing in response. Both of them were too caught up in the endless cycle of eating that they hadn’t noticed the other changes taking shape around them. The throne room looked dimmer than it should have, their massive bodies blocking some of the windows.

“What’s going on?” Carnation asked, all but dragging her brother backward a few steps when Celestia’s flabby body surged forward a few centimeters.

“Magic.” Marjoram rasped, “But I’m not sure what kind.” His voice was trembling. It was clear this was shaking him down to the core. He used his magic to take a dose of medication from his inhaler, obviously working to keep himself calm. “They’re not listening to us.”

“No, they’re not.” Shores sighed, coming down to land near the pair. Grimacing as both princesses seemed to gain a little more even as they watched. “We should get going-”

The double doors at the end of the throne room burst open, allowing a group of ponies to gallop inside. When the real chaos began. Shouts of despair, arguing, talking, introductions.

Celestia was aware there were ponies in the throne room, but she’d left instructions with the maids to impress upon ponies that came to see her and Luna that they’d only take visitors after lunch.

Celestia opened her mouth to accept another cupcake. Not minding one bit as frosting smeared across one of her chubby cheeks and stained her muzzle. Not noticing, or caring, that Starlight and Trixie were trying to catch her attention. Only murmuring a few placid platitudes by way of explanation.

She didn’t notice when the group left. Didn’t realize when her maid became too fat to walk. Didn’t notice the castle falling into disarray around her.

The palace was filled with some of the fattest ponies in Canterlot, and she didn’t mind. Didn’t quite understand what that meant, even as Canterlot as a whole started to be more affected by the weight of its citizens.

Neither princess noticed or cared. Bathing in the light of the stained glass windows, happily eating away. Not bothered by their expanding waistlines in the slightest, all that mattered to the two princesses was eating their next cupcake.

(LINE BREAK)

If ponies were in their right minds, they might have noticed how Canterlot was changing.

It was a mountainside city, originally picked out because of the plentiful clean water and resources hidden beneath the mountains surface. The refugees of the Everfree City had chosen well, and a temporary city had grown to become the Capital of one of the most powerful countries in the world.

There were...issues with the city, however. High population density for one. Because the city had been built on a large, natural shelf jutting out from the mountain’s side, it meant that there was limited space for buildings and expansions. The high towers of Canterlot’s high ranking buildings weren’t just for an exciting skyline: they were meant to save space.

Ancient unicorns had worked hard to build supports under the city, earth ponies adding their own magic to the stone beneath the city. Shoring it’s strength, adding onto the existing shelf as much as possible to give the fledgling city the strength and space needed for it to be viable.

As the citizens of the once fair city grew, space became an issue. More of an issue than usual.

Pavement cracked. Ancient magic flickering as it fought against forces and weight that it simply wasn’t meant to hold. Buildings were abandoned, as were high towers.

To anyone who was paying attention, they could see Canterlot starting to lean, or sink. Perhaps both. The supports were holding, still strong, but there was only so much weight they could handle. As buildings stopped growing along with the memories of inflicted ponies, ponies began to outgrow buildings. Laying out in the street, never stopping their endless munching.

Celestia was unaware of these changes. Though she should have known. Tapestries and the chandelier were leaning to one side. Leaning away from the safe mountain that the city had clung to for so long, and towards the valley below.

The cupcakes were as excellent as they had always been, Celestia noted dimly. Swallowing an icing laden cupcake with a sigh. They were always so good-

Her flanks jumped out several inches, swelling with new fat. Sending ripples of motion across her body. Celestia shivered, feeling her rump press against the stained glass behind her. She could feel the glass bending. Not broken, but fighting with her enormity to keep it contained.

Outside, not that Celestia could see outside, a pink sky had replaced the normal blue. Swirls of heavy magic, holding hundreds of thousands of cupcakes aloft darkened the skies. Not quite blotting out the sun, but it was surreal to see.

All the citizens of Canterlot were slaves to their hunger. Endlessly eating the fattening cupcakes that were putting their lives in danger. Not because their bodies were failing, or because their fat made it impossible to breathe. The magic Discord wove made it impossible for those things to happen.

What Discord’s magic hadn’t intended, however, was the mountain town collapsing under the weight of its citizens. It didn’t know how to prevent that from happening.

And yet, nopony cared. Nopony came to fix things. There was no one mobile enough to do any of that work.

A couple dozen cupcakes later, and Celestia’s rear broke through the window panes. Spared the falling glass, her white, flabby rear spilled out of the new openings.

Across the throne room, Luna’s own rear was doing the same. Threatening to destroy the wall behind her with her plot alone. Fat oozing over the crushed window sills, competing for space as it always was. The throne room was rather dark now, the princesses were now big enough that their bodies blocked all the sources of natural light, leaving only the leaning chandeliers to try to light the space by themselves: a task they’d never been meant to handle.

Celestia and Luna roughly took up half of the throne room each. Their hooves were gone, sucked into the sleeves of fat that had once been their legs. Celestia was larger than Luna, her head looking comically small in comparison to the spare tires where her neck had been. As she ate, a roll started to encroach on her head.

It wouldn’t be long before the fat really started to swallow up Celestia’s head. Creating a tunnel of fat that the cupcakes would have to travel to to get to her mouth. As Celestia chewed, the roll started to become more prominent. It wouldn’t be very long at all before Celestia stopped looking like a pony entirely.

Luna would be spared that fate for a little while yet. As she ate, her body continued to expand outward. Her tail was swallowed up, lost between her plot cheeks. Another cupcake, and there was a breaking of glass. Luna’s rear had pushed the glass from the window panes and was now spilling out from the windows.

Canterlot was looking worse for wear, all over. Fattened citizens blocked the moat (primarily the city guards who were on patrol at the city’s entrance), causing water to flood the lower sections of the city. Dousing those who lived there, and speeding up the decay. Making things look worse for wear within a matter of days, much less months.

Canterlot’s supports were holding well enough for now, but they wouldn’t last much longer. The city was already starting to shift and sink. Roads and buildings buckling under the obesity that reigned all of Equestria.

No building was spared the slothful destruction of hundreds of thousands of pounds. Windows broke as fat pushed them out of their panes, doors splintered against flabby rears and bellies.

Buildings were pushed off kilter and sent down the mountain as fat pushed them off their foundations. Immobilized, house-sized fatty blobs broke their houses from the inside, crowds of them growing into each other. Not aware of the destruction, but their flabby bodies expanding over the evidence like the rubble was the finest cushions available.

Carts, toys, wagons, all sorts of things were starting to roll towards the edges of the city. Some broke guardrails, falling off to shatter against the buildings wrecked below. Others were trapped in between the immobile ponies that clogged the streets, quickly being demolished under the growing enormity of the ponies they were stuck near.

The two royal sisters ate on. The only sounds ringing through the palace were that of their own eating, and the creaking and groaning of a city that was starting to crumble to pieces around them.

(LINE BREAK)

Canterlot shook. Breaking Luna’s muddled, gluttonous thoughts for a few moments as things seemed to shift. The chandeliers rattling, the ruins of the palace groaning. Banners moving at the movement of the ground.

The palace was an empty shell. Once it had been a carefully crafted machine meant for all sorts of ponies to live and work. For dignitaries to meet, grand parties, and for all sorts of things. Discord’s magic had erased hundreds of years of hard work, turning everything (even the castle gardens) into the throne room. Allowing Celestia and Luna to keep growing unimpeded.

The two massive mares moved too. Their obese bodies quaking as one of Canterlot’s supports failed.Falling into the river below with a massive crash that could be heard across Equestria twice over.

The city shuddered, water once again dispersed as the city fell a few inches. Bodies jiggled, a few more buildings crumbled, yet nopony noticed. The sudden movement caused belching and burps to be heard all throughout the city, but that was the only thing that changed.

At the edge of the city, the edge where the shelf met the mountain proper, a crack was forming. It had been caused by the flooding, originally, but as the citizens of Canterlot grew into massive blobs, it was another sign of things declining.

The city was falling apart, inside and out. The great, iconic towers of Canterlot were all but gone. Fallen to the valley below, nothing more than ruined husks of splendor. The splendor of the city was gone, hidden under the corpulent bodies of its citizens.

And still, the eating never stopped.

A great distance away, Trixie and Starlight watched the support collapsing from the hills outside Ponyville. Wondering, with growing horror and worry, if Canterlot would be able to support its citizens for much longer.

(LINE BREAK)

The palace was gone. Destroyed from the inside by it’s immensely huge denizens. Luna and Celestia didn’t mind one bit, in fact they preferred it. The windows to the outside had been blocked by their fat for months, so being able to see and feel the sunlight was a boon. Celestia got to see the waterfall, when she bothered to be aware of it. And Luna could look over the destroyed city to see the valley stretching out below them.

Neither of them paid much attention to their surroundings of course, it was just the spirit of the thing. The illusion of choice.

If Luna paused in her never ending feast for a few seconds, and squinted around her balloon like cheeks, she could just about make out two new mountains on the horizon. Joining the six, multicoloured mountains nearby. Different from the others, some instinct told her, but she couldn’t figure out why. One was a pale blue, and the other a light purple.

She didn’t of course. Wrapped up in her empty pit of a stomach, she did nothing but try to fill it. Gorging herself on massive amounts of cupcakes, focused so solely on this task, that she didn’t seem to feel her plot rising high above her head. Not quite squished against the mountain behind her, but it was close.

The city was crumbling underneath them, and they had no idea.

There was a noise, like rocks being broken open by a hammer. Sharp, and loud, and ringing. A second support had given out. The occupants of Canterlot were jostled from their stupors for a few moments, belching loudly enough it could be heard in Ponyville. Bodies shaking and quaking.

And the sound again, only ten times worse. The crack along the mountain edge completed it’s edge as the last of the supports gave way from under Canterlot. Leaving the city suspended in place for a fraction of a second, before gravity took its toll.

Thankfully, Canterlot didn’t tumble down the mountain in a great many pieces. It slid down a few hundred feet, before being caught by a mixture of rubble, the remnants of the shelf that had held up the city for generations, and the rubble caused by the city’s fall.

The shelf that Canterlot had been on was heavy, after all. Thick, reinforced with old magic. It held together alarmingly well, considering the circumstances. Even though roads were cracked in two, the city was still roughly in one piece.

The ponies of Canterlot were unharmed, merely jostled. Burps being forced out of them because of the rough landing. The belching could be heard throughout Equestria. Even the princesses belched alongside the common folk.

The city, in the aftermath, was more unrecognizable than before. Hunks of the city’s underbelly were gone, smashed and torn away from the impact. The city's descent had scored great wounds on the mountain’s edge, causing most of the rubble that had saved them. The waterfalls were different, now, too. Parts of upper Canterlot starting to be flooded since the city had shifted position again. Lower Canterlot would still be flooded, but so too would be where the palace had once sat.

Water rushed between the two princesses. Cleansing the lower rolls of their bellies from the rock dust that coated them.

Celestia noticed this in passing, feeling pleasure in the cool water rushing past her. But took no more notice of it than someone might have noticed a pleasant breeze. Only opening her mouth for the next cupcake. With all the rocking and jostling, they had to have ordered a massage. Which was why they’d moved about so much before. Maybe that masseuse from Ponyville..oh what was his name? The bulky pegasus...Thoughts like leaves in a hurricane. Celestia quickly forgot about the movements.

Luna, on the other hoof, was waiting for her next cupcake. Mouth hanging limply open without receiving one for a few moments was shockingly different. So she looked up. Expecting the streams of cupcakes to be right there, where they always were.

She’d been jostled a bit more than her sister when the city fell. Her rear had been touching the mountain, after all, squishing into it with its heft. Thankfully her massive, fatty rear had been saved any pain or damage from friction, but it made her rear settle differently over the rubble it had been covering for weeks. It was nice to feel a breeze, gentle and quiet...Now where were her cupcakes, it was rude to leave her waiting.

Luna’s head was stuck in place because of the fat starting to encroach on her head. Immobilizing her head, she could just crane her eyes upward to look. Hardly able to see very far up at all because of her fatty neck, as well as the beginning of a tunnel of fat that was starting to form around her head. Her head was already half-sunk into her neck, it wouldn’t be much longer for the fat to overtake it completely. Celestia was worse, head gone from visible view. Not even her muzzle poking out.

The cupcakes weren’t where they were supposed to be. The pink sky was as pink as ever, and the clouds of cupcakes were as dense as always. They were just hovering where they used to, above the city’s skyline from when the city was still resting on its original foundations. Some were already making their way down, hence Celestia eating a cupcake, but the vast majority hadn’t started to move yet.

They were migrating, moving downwards to meet their fellows in their hundreds of thousands. Temporarily blocking out the sun with their sudden movements.

For a moment, less than a fraction of a second, Luna saw what the city had turned into. What she and Celestia had turned into, and it made her heart cold with dread. She could see the mountainous blobs of those in the distance, of good ponies who had fought for Equestria’s freedom-

A cupcake pressed against her lips, and Luna ate it. Mind cleared of her thoughts, she took no more notice to the scenery than to wonder if there was going to be another flavour change up soon.

Across from Luna, Celestia gorged on. Unable to move under her own power, with the exception of chewing and swallowing.

Neither were as large as some of the ponies that decorated Equestria’s surface. But they were still growing. Looking more like shapeless, fatty blobs with every cupcake that passed through their lips.