Soarin can't stop cumming. While he is freaked out, his partner just keeps saying, "More..."

Soarin’ groaned. His lower body was pinned to the mattress by the weight of his massive cock, though his jerking hips were definitely making an effort to do otherwise. His entire body, in fact, was dominated by a mix of warring emotions - pleasure, confusion, fear.

Soarin’ had started cumming four minutes ago. He hadn’t stopped since.

He groaned again as a fresh spurt roared up his shaft, pumped up against gravity by the powerful muscles of his cock. His beanbag chair-sized balls churned and throbbed. Out of the corner of his vision, he thought he could seem them bloating even larger as he came, swelling larger and larger until they not only had pushed his legs fully apart, but also rolled over them like the massive pillows they were.

But they weren’t near the most massive kind of equipment he owned. Breathing heavily, Soarin’ let his eyes wander up. Starting at his twitching, pulsing crotch, he took in the sight of an enormous shaft the width of a small tree. It absolutely dominated his hips, and his eyes followed it up - throbbing veins and stretched, musky skin - up and up and up until they came to the medial ring, so high up that a fully grown mare could have hugged it only by standing up on her hind legs.

Up and up and up. And then, finally, after six feet of thick stallion cock, he saw her legs again. Rainbow Dash’s hooves dangled against the sides of his obelisk of stallionhood, kicking helplessly in the warm, musky air.

“Dash,” he said, his voice coming out as a dry croak. “I - it’s not stopping. It should be stopping. Right?”

Dash mumbled something, so quiet he couldn’t hear it. Soarin’ squinted up at her, and realized for the first time that she was holding something in her front hooves. A heartbeat later, he realized what it was. Speared on his massive, tree-like cock, her snatch stretched wider than any reasonable pony’s hips, Rainbow Dash had had gallons and gallons of cum gushing into her nonstop for the past four - now nearly five - minutes. The thing in her hooves was her stomach, her womb pumped so full of hot pegasus cum that it had actually began to swell and grow. By now, he could just barely see that it was spilling over her hooves.

She mumbled the same thing again. “What?” he asked hoarsely. “Dash, I - “

“More.” This time, the syllable was unmistakable. Soarin’ blinked, grunted as another surge swept through his cock. He could see Dash’s tummy bulge as the flood splashed out inside of her, her tight pussy somehow managing to keep every drop of his steaming hot seed inside.

“Dash - “

“More!” That was the Dash he knew: demanding, hotheaded, and - lustful? The arousal and need in her voice were impossible to miss. Dash just moaned and moaned, pleas for more and more cum slipping out of her muzzle as Soarin’s cum pumped and throbbed inside of her, spilling gallons more of his seed to fill her womb and belly.

“Dash,” Soarin’ said. “I don’t think this is good. I think we should - ungh - try and stop.”

“More,” Dash moaned. “Fill me up! Fill me up till I damn well burst! More, more more!”

Soarin’ groaned as his balls suddenly churned even harder, an impossible tightness welling up at the bottom of his shaft. As his eyes fluttered open, he noticed the pony-sized bulge at the base of his cock, the veins around it twitching and throbbing as it slowly traveled upward…

“No!” he said. “Dash, you have to get off!”

“Yes!” Dash’s head rolled back, her hips working even more tightly around Soarin’s cock to milk him for all he had. “Yes, yes, yes.”

The bulge reached the medial ring, reached the bottom of his flare, reached the tip - and exploded inside of Rainbow’s cunt.

She all but screamed in pleasure as a two barrels’ worth of cum flooded inside of her. It crashed up into her womb, and soon her stomach was swelling out even further in size. In three seconds, it’d doubled in size; in five seconds, tripled. Soarin’ just grunted, his hips jerking ineffectually as he watched Rainbow Dash become little more than a condom for his monstrous tool, with her massive, drooping belly growing so large and heavy that her hips actually slipped down his cock, her body somehow stretching even wider to take a good foot of him inside of her.

“More,” Rainbow Dash murmured, almost sleepily. “More.” Her belly was twice her size now, but it didn’t sound like she wanted him to stop anytime soon.

As his balls sloshed and swelled, soon coming to weigh down on part of Soarin’s stomach, he began to fear that she truly would get her wish.