Twilight was in no hurry to begin. The careful strategist knew not just herself, but the 'enemy' as well. While she had no doubt of how this duel of theirs would end, it would be cute beyond words to watch Trixie try so very hard. In fact, the poor thing was still trying to shout orders gently enough for Fluttershy to obey. If only she had studied more, she might have known the old saying: you can lead a pony to cock, but you can’t make them drink. Ah, well! There was no rush to win here. She could wait a few minutes before starting, if it meant she could watch and enjoy the show.

Pinkie, however, did not know how to wait. She had been out sick, from too much candy, the day her class had taught the meaning of the word. She bounced anxiously on both hooves, ready to start five minutes ago. “Come ooooon, Twilight!” she begged, her tongue lolling like a puppy waiting on her treat. “They’re getting ahead of us! You’ve got your princessly pride on the line! We can’t let them win!”

“Alright, alright,” Twilight said, grinning tenderly even as she shook her head. There was still no hurry, but Pinkie’s enthusiasm bordered infectious. “We’ve given them enough of a head start. Why don’t we show Trixie what real teamwork can do!”

Pinkie’s pink-as-pink mane began to glow a bright lavender as Twilight’s magic pressed down on her, gentle but firm. Eager as she might have been, Pinkie was just too hyper a pony to sit and stay sat. It took work to bring her to her knees, like coiling a spring; a force of personality equal to the unimaginable energy of a chubby party pony. Twilight had no trouble with that, of course. The smile on her face was pure confidence, a simple, serene expectation that the whole universe - Pinkie Pie included - would bow down before her if it meant even a taste of that divinely magnificent cock.

“So, so, so excited!” Her partner giggled and snorted with barely-restrained anticipation as she bent slowly down, drawing face to flare with Twilight at last. She took a deep breath, savoring her best friend’s potency like she would a freshly-baked cake, dreaming already of how warm and satisfied and full it would make her. Oh, she just couldn’t resist any longer! She leaned in and gave it a big, sloppy kiss, shivering in delight as her lips met Twilight's broad cumslit in a passionate, sticky embrace. “Mmm-mmm-yuh!”

“Ooh!” Twilight sighed. Her hips lurched instinctively forward as shocks and tingles of pleasure shot up her spine. The royal dick stirred slowly at Pinkie’s touch, a giant awoken from its drowsy slumber. Purple-furred balls the size of her best friend’s amply-fed tits (if not bigger!) drooped lower and lower as they filled with heavy seed. Twilight had gone whole hours without emptying a load into one of her loyal subjects, just to prepare for this contest, and she was feeling awfully pent-up right now! Beneath her calm, royal grace lurked a powerfully sexual beast, endlessly hungry and impossible to sate. To deny it anything was just begging for trouble, and a tremendously full belly of cum besides; exactly as planned.

“Mmm…” She bucked her hips forward yet again, her oversized rod all but pulling her along with sheer need. Pinkie’s eyes widened in happy surprise, cheeks bulging as her tender kiss became so much more. Twilight’s colossal cock simply commanded space, imposing itself easily on Pinkie’s mouth as she swallowed it down. The audience gasped as they saw an unmistakable bulge surge down her throat, their princess’s fat medial ring forming a neat seal at the top of her gullet - an impossible meal for any pony but Pinkie Pie. “Keep that up…”

Pinkie gurgled her own confirmation, eyes full of love as she stared up with absolute trust (and absoluter cock-hunger) at her best friend in the world. A warm, satisfying saltiness flooded her tastebuds, her tongue running up and down that immense shaft for every last taste and sensation. A moan from above marked Twilight’s approval, her arousal flowing down Pinkie’s throat like a thick, hearty soup. She wrapped her arms around Twilight’s steady thighs and held on tight, her fingers squishing into those soft, ripe seedpods as they bloated up still bigger. Deft baker's fingers pleaded and pleased the source of her favorite frosting. This was going to be a bumpy ride!

The first orgasm was explosive, a tidal wave of lewd excess. Twilight was an enormously efficient pony, productive in all sorts of ways, and her body had put the last few hours to very good use. Gallons and gallons of rich, creamy cum poured down Pinkie’s clutching throat, every drop not deposited straight into her bottomless belly slurped up by her questing, squirming tongue. A normal pony could hardly have held it all in, but Pinkie was built to stretch and this wasn't nearly her first time at the rodeo! Her leotard, already fit to burst from holding her pre-orgasm figure's fullness, began to rip and tear. The material groaned audibly as her belly blew outward, pudgy pink flesh oozing through the shiny black material.

Streetch, snip, snap. Twilight watched with quiet interest as the final straps of Pinkie’s outfit failed to contain her. She was expanding in earnest now, her beautifully bulging belly so swollen and engorged with potent, goopy cum the audience could see it from behind. It was just like watching a water balloon fill from the tap; every tense, every twitch of her heavy, pendulous balls reflected in the gallons of thick, creamy cum pumping into her friend’s burgeoning form.

And that was barely half of the full proceeds. Pinkie had always had a positively prodigious metabolism, digesting cakes and burning through calories so fast she could nearly plump up in real time. A good thing, too, Twilight thought, smiling and eying Pinkie’s ever-thickening rear. If she couldn’t, she might have popped by now.

But a good scientist left no limit untested, no boundary unbroken. She simply had to see just how much Pinkie could take, considering just how much she had left to give... “Hope you enjoyed your appetizer, Pinkie~” She sighed and bucked her hips, curling her fingers in Pinkie’s mane as the next wave of orgasm broke over her. Spurt after splattering spurt of piping hot seed, made with love, flowed fresh down Pinkie’s throat in an endless stuffing stream.

Pinkie’s grip tightened, too, arms tightening around Twilight’s long, tensing legs in a loving hug. She couldn’t speak, of course - her throat was occupied with far more important business - but her eagerness for more showed in every drop she swallowed. A slow, rubbery, stretching sound filled the air as her cum-filled tummy reached earth, more and more Pinkie pudge swelling and pooling over the floor by the second.

“Ah…” Just as it looked like Pinkie would pop, there was a calm in the sticky storm. A calm in the horny hurricane. Twilight pulled herself from Pinkie’s mouth with an extended wet schlick. They weren’t done yet, not by a long shot, but Pinkie needed a half minute’s break to rest and digest, and Twilight was more than happy to oblige.

She glanced casually toward the other side of the stage, letting out a bemused chuckle as she checked on The Great and Powerful Trixie’s poor and pointless progress. The hourglass was still running, but seeing how slowly Fluttershy’s unsatisfied belly was filling up, it would hardly matter how much time they wasted. By the time Twilight was finished, there would be no doubt whatsoever who the most virile, most productive magician in Ponyville was. “Thank you, Pinkie. That certainly took the pressure off!”

“Oh, my pleasure, Twilight!” Pinkie said, springing bouncily to her hooves. Not even Twilight could keep her down forever. She licked a heavy dollop of precious spooge from her lips, doing her part as partner to swallow up every last drop of gooey, salty seed. Years and years of cake-baking and licking the spoon had made her a lingual pro, and not a molecule of delicious Twicum would end up anywhere but her belly if she could help it! With a hasty Pinkie Promise to herself - and to that pretty prick! - she swiveled around, wiggling her magnificently plump pink patootie right where Twilight’s colossal cutie-conqueror would be sure to find it. “But we have to keep going! Who knows what sort of evilly evil things Trixie could be planning if she wins. We just have to beat her, Twilight! No matter what!”

“Good thinking!” Twilight nodded. They didn’t need to go so far as this to win, but filling Pinkie up with even more thick cum could only be a good idea. The science of bubble-butt bloating virtually demanded it! The tip of her needy pony-poker was already testing the new waters, smearing Pinkie’s cheeks with a musky sheen of pre. She took a good handful of Pinkie’s doughy hips, fingers sinking deep into plush, warm flesh. “We can’t let Trixie go thinking she can win, now, can we?”

“Nuh-uh, no we caaaa~aaan’t!” Pinkie squealed, her eyes full of stars and her hair all but sticking on end, as Twilight bumped her hips up and plunged into her needy puss. Oh, golly gee! Twilight had filled her throat up just fine, but this was a whole other game! She could feel every firm throb of Twilight’s beating heart through her cunny-caressing veins, every last inch of that overwhelming cock as it filled her to no end, touching and loving her in all the right places. Her eyes rolled back into her head as Twilight kept going, deeper and deeper, the proud medial ring stretching her further still as it finally slipped inside her slit. But even Twilight’s cock wasn’t endless - hard as it was to tell sometimes - and finally, finally her hips met Pinkie’s with a gentle, welcoming slap. It was a soft collision, like a mouse running into an elephant, but the cute little smack of purple flesh against pink might just have sent Pinkie over the edge.

“Mm, I don’t know, Pinkie. It seems like you’ve had a lot already.” A pony might have sworn that, even with her belly so bloated and stuffed full of cum, the battering ram bulge of Twilight’s flare could still be seen poking through Pinkie's pumped and plumped stomach. Only for a pony as stretchy and pliable as Pinkie Pie would that have been even remotely possible. Rubber wasn’t just a material for party balloons, but for condoms. A pink pony of a party condom, perfect to wrap around a princess’s prideful prick. Twilight smiled, firm fingers nearly disappearing into Pinkie’s squishy rear as her body processed load upon load of nutritious cum. “But you want still want more, don’t you?”

“More!” Pinkie squeaked, squirming and straining around her burgeoning chest to cradle her swollen tummy. She was no longer concerned about winning. All she wanted now was everything Twilight could give her. Every part of her felt so sensitive, so vivid. So alive, like the world’s biggest party going on inside her! From her fat nipples, pinker than pink, to her heavenly soft hips, she felt so weighty and hefty now, and all of it thanks to Twilight’s thick, rich, pony-plumping cum. And it only felt better the bigger she got. “I need it! Gotta have it! More cum, more cock, more, more, more!”

“More? Hmm, I don’t know...” Twilight grinned impishly, seesawing in (smack!) and out, in (smack!) and out, like waves building up on the shore. She glanced to the hourglass, running down and down and down to its final grains. She upped her pace and Pinkie tensed, the wet, velvety sleeve of her cunt thirstier than ever for a fresh load. Faster and faster, deeper and deeper. This one was going to be the biggest, bestest yet.

“Come on, Twilight, please!” Pinkie whimpered, the need burning inside her. She felt so empty, so unsatisfied, and there was only one cure for it: the phallic princess prescription. “Please, please, please!”

“Ah…” Twilight could feel the tsunami building up inside her, sloshing to and fro between her legs. To fill or not to fill… Hardly the question at this point. It wasn’t entirely up to her anymore! “Okay, Pinkie, since you want it so bad, I’ll give you more. I’ve got plenty left, of course. More than Trixie could build up if she had a week. Bathtubs, lakes, oceans of cum, and all of it for you! Because we’re friends. So I hope you know what you’re asking for, Pinkie…” She shivered in pleasure as gallon after gallon began the long journey through her impossible shaft, the overwhelming sensation of orgasm blossoming deep inside her. “Because, ready or not, here it cums!”