Vore piece of Blueblood, already fat from eating and digesting the Mane Six, eating Celestia and Luna and digesting them, not realizing he's pretty much doomed Equestria...

“Blueblood,” Celestia said. “Would you happen to know where Princess Twilight’s gone?”

Blueblood smirked, his chubby cheeks folding in on themselves. His overstuffed tummy growled as he eyed Celestia’s curves, her belly, her wide-spanning flank. “I might,” he said. “But you’ll have to come closer.”

“Really, Prince Blueblood,” Celestia said, walking closer. “I’d prefer not to play any games with you today, so - “

Before she could even finish her sentence, Blueblood had snapped into action. His belly might’ve touched the ground and wobbled with his every step, and he might have had chins enough to put any sumo pony to shame, but somehow, that pony moved fast. Before Celestia knew it, he’d seized her in his hooves and slammed her against the wall, holding her captive with the weight of his gigantic belly.

“They’ve become fat,” Blueblood sneered. “Mine, specifically. And you’re about to join them, dear Auntie.” Though Celestia struggled, she was powerless to stop him as he lifted her up in the air and, in one, swift motion, shoved her head down his throat.

She twisted and turned, squirming in his throat as he slowly gulped her down. He felt his jaw widen to take in her shoulders, his belly growling even louder to make its excitement known at taking in this new, larger meal. He’d so loved the way each of those precious little Elements of Harmony had squirmed and shouted on the way down, tickling his throat as his belly prepared itself for each new occupant. He loved the way his fat arms and thighs jiggled as he sat back on his haunch with a powerful thud before forcing Celestia down even further.

He managed to get his mouth around her chest, gulping even more fiercely as her head reached the top of his stomach. His neck bulged obscenely around her front legs. Now that he’d gotten over this hurdle, though, the rest was going to be a piece of cake - and once he’d gotten the image of cake in his mind, his mission to add his larger aunt to his generous and growing curves became something more like a crusade.

He moaned as he felt her thighs slide between his gums like butter, gulping her down greedily as his belly expanded around the rest of her body. She finally slid down into his enormous stomach with a final squirm and a shout; by now, his gut protruded so far out from the rest of his body that it would have lifted him up a few inches into the air had he tried to get up off his fat flank. As it happened, though, he was more than content to just sit there, smacking his lips as his meal settled.

“Sister!”

Blueblood turned almost lazily to face the open door of his bedroom. A shocked, furious Princess Luna stood there, watching him with fiery eyes.

“Your sister?” he asked. He patted his formerly flabby stomach, which was now stretched tight over the soon-to-be-fat form of Princess Celestia. “Oh, she’s doing just fine.”

“Restore her, you fiend!” Luna charged at Blueblood, her horn crackling with a dark blue, nearly black light -

- And Blueblood swung himself up and over his gigantic belly, tackling Luna to the floor with a crash. He grinned as he looked down at her, his fat little legs wobbling on either side of the massive stomach he’d used to pin her to the ground. She struggled, grunting and cursing, but it was no use.

In the blink of an eye, Blueblood had rocked himself forward and seized Luna by the shoulders. She came speeding back with a shriek on the rock-back, though any sounds of struggle were quickly muffled as he gulped her down even more quickly than he’d swallowed her sister.

When he was finally done with his meal - dessert, he joked to himself - he took in a deep breath and smiled. His enormous belly was stretched as tight as a drum, now protruding a good six feet out from the rest of his body. He groaned, feeling his stomach churn as it started to digest his incredible meal. He could already imagine turning the two great “Princesses” into his gut fat - or maybe, he mused with some foal-like amusement, his ass fat, able to remember their squirming struggles every time he shifted on his massive flank. He could only wonder how beautifully enormous he’d be when he was finished.

With a burp, two crowns flew out of his mouth. They each hit the ground with a clink: one, a golden tiara, and the other, a simple silver circlet. Blueblood held a hoof to his mouth sheepishly. He could already feel the post-stuffing drowsiness coming on.

As Blueblood snored, more and more beautiful fat slowly flowing out to fill out the rest of his already enormous figure, the rest of Equestria slowly looked up at the sky in wonder, confusion, and fear. Above the land, the Sun stood perfectly still; below it, the Moon waited for a dusk that would never come.

Six hours later, Blueblood wobbled to his feet, his enormous belly scraping along the floor as he walked, and waddled to find his next meal.