A black pegasus looked over the porch of his cloudhouse at the chaos in the town below. A mare was dragging enormous, mattress-sized breasts behind her, followed closely by a pair of dragons trying to latch onto her nipples.

"I sure am glad I'm not out there," Thunderlane said, happily tempting fate. He was sure whatever was happening would soon be fixed by Princess Twilight, and if not, he had a stocked pantry and enough survival gear to last through any disaster. His brother was fast asleep in his bedroom. 'Might be trouble when he wakes up,' he thought, knowing how he'd worry about his friends.

"Thunderlaaane!"

He recognized the voice and turned, seeing two ponies flying towards him.

Flitter and Cloudchaser. He used to date them, well, one of them, then the other, then both… Threesomes are awkward, they decided, and broke off amiably. Now here they were, wings beating irregularly, eyes open wide, with a peculiar smell hanging about them...

"Thunderlaaane!" They cried, "We neeeeed you!"

Thunderlane immediately turned around, realizing they were being affected by whatever was going on, and began to bolt inside, only to be thrown to the ground as the two mares glomped his perfectly toned backside.

He struggled to get up, but the two seemed to be stuck fast. Their hooves massaged his ass, and he had to admit it felt pretty good… Turning his head, he gasped at what he saw. The light grey mares had begun to darken, turning to his own dark shade. They also seemed rounder, plumper… Their features were shrinking and melting together!

He tried to scream, but nothing would come out. He could barely think straight, and the mares-cum-ass weren't helping as their thoughts flooded his mind. Unlike the other victims, he was invaded by the full consciousness of two ponies at once, and even a great mind, which he most certainly was not, would have trouble fighting off this assault.

The twins' desires overwrote his own hobbies. Weightlifting was replaced by cardio, cloudbusting by sculpting, and the love of beautiful girls with a burning desire for a big, strong stallion to ride him like there was no tomorrow.

Thunderlane stood up shakily, hooves unused to the massive weight of his backside. Between his legs, his turgid manhood throbbed. He needed a colt, now!

"Big bro?! What the hay happened?!"

Author's Note

I just realized that I'm probably going to lose a lot of followers for this. Let me just make clear that this story does not reflect any possible future continuations of Golden, Princess Blubberbutt, or Fattyville, nor, most likely, any other future writings. I just had some sick shit I needed to get out.