Applejack gasped as she felt Troubleshoe’s cock poke against her backdoor. It was wide - almost half as wide as the hips it was trying to enter - but through some impossible kind of geometry, it finally slipped through.

Applejack melted around it. “Oh….geeze. Oh, geeze. Oh, Celestia I’m so full.”

Behind her, Troubleshoes looked sadly down at his stallionhood. It was fully erect, and bigger than any package that either Applejack or Big Mac - who was standing on AJ’s other side, his eyes wider and his cock harder than ever before in his life - had ever seen. “FIllin’ up a mare with just the head. Just mah luck.”

Applejack’s eyes widened. “That’s… You tryin’ to say that’s just the head?”

“Yup,” Troubleshoes said glumly. “Looks like that’s gonna be it for - “

“Now, don’t you talk crazy-like!” Applejack grunted around the enormous horsecock filling her and turned her head around to look the much larger stallion in the eye. “You’re gonna fill me up good with that thing, and you’re gonna do it all the way!”

“All the way?” Troubleshoes said. He blinked slowly.

“All the way! Ain’t that right, Mac?”

“Y-yup! Eeyup!” Big Mac nodded frantically. One of his hooves was already rubbing his own stallionhood fervently. Two feet long if it were an inch, “Big Red” stretched all the way from his dangling, grapefruit-sized balls to near the bottom of his chest. But Troubleshoes was something else. He already stood near two feet taller than Mac - already an oddity in Equestria - and his massive, pre-dripping shaft stuck out in front of him by a good thirteen inches.

Applejack grunted as she forced herself back a little more. Somehow, impossibly, her ass opened up even wider, allowing the last of the head to slip inside of her.

“Better,” she grunted, sweat rolling down her forehead. “But I need more.”

“M-more?” Troubleshoes said. He suddenly looked worried.

“More!” Applejack barked. “Don’t care how, don’t care why - just do it!”

On command, Troubleshoes got busy, and he got busy fast. With a single thrust of his enormous hips, he shoved the rest of his cock inside of Applejack. AJ groaned and moaned and squirmed as he speared her on his shaft, the medial ring squeezing its way inside of her and bulging her stomach and chest out obscenely as it rudely pushed its way past her internal organs - and then went completely silent.

Big Mac stared, paralyzed and nearly stark-white, as the meaty, oozing tip of Troubleshoes’ cock twitched from between Applejack’s jaws. Applejack let out a short, gasping whine, but Troubleshoes didn’t seem horrified. Only sad.

“Another pony too small for ol’ Troubleshoes,” he said. He turned to the side, Applejack’s speared body lifting off the floor and swinging with his massive stallionhood as it slapped against the insides of his legs. He frowned sadly. “Looks like my cocktip’s gonna go cold and pent-up again.”

Big Mac saw his sister speared on another stallion’s rod like last night’s kebabs. He saw what looked to be easily pints of precum already dribbling out of Troubleshoe’s throbbing cock. He saw his sister’s bulging belly, stretched out to its limits just by the size of the shaft it contained.

Lil’ Big Macintosh saw the chance of a liftetime, and took it.

Without even taking a moment to hesitate, he lurched forward and kissed Applejack right on the muzzle. She moaned, a low, vibrating sound as their lips met - and Mac moaned in return as he felt Troubleshoe’s massive flare enter his mouth and poke the back of his throat. The two mashed their lips together, Big Mac loving his sister’s taste almost as much as he loved the taste of Troubleshoe’s cock. He went back and forth, pulling away from Applejack’s lips with a wet pop, though whether it was from saliva or Troubleshoe’s pre it was impossible to tell. Then he dove right back in, kissing and pulling back, attacking and retreating, choking and breathing.

Troubleshoes just gasped, held a hoof to his mouth, and -

Came.