Amily is a compact, thick-pawed, chonky  feral pet gryphon with enormous potential for growth and corruption. Shi is only two feet tall and three feet long on all fours, and can move about with hir massive breasts, huge balls, and big sheath with ease. Incredibly breedable, Amily can be impregnated and give birth in seconds, or breed others just as fast. 
Toby is a young fox boy who was playing in his back yard when Amily finds him. He hasn't experienced puberty yet, but as he spends too much time near Amily, he will become hyper-endowed and excessively horny very fast. 

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Toby sat on the edge of the forest. The boy wasn't supposed to play there, and he knew it, but the woods behind his backyard called out to him like a siren song. There was just something about the wild. He liked the way the air tasted, the sound of the wind in the leaves, and the smell of the forest floor. Toby took a deep breath, and stood up from where he'd been sitting on a stump. It was starting to get dark, and the moon was already showing through the trees. He should probably go inside now, and not get lost.
Just as he was about to turn around, he heard a sound. Toby froze, not sure if he should run or not. A twig cracked, and the fox turned toward the sound, looking through the dim forest. His eyesight wasn't good enough to pick anything out, but it seemed that something was coming closer.
"Hello?" he asked softly. Toby had always heard that if you didn't move, a predator would assume you were a rock or a tree.
He heard another crack, and suddenly the undergrowth in front of him rustled. Toby stepped back, heart beating hard, as something came into view. He blinked, trying to understand what he was seeing. It was a cat. A really big cat. Or so he thought at first. 
"Oh." Toby exhaled, shoulders sagging. "It's just a big house cat."
The creature paused, and Toby got a better look at it. It was a big cat, a tiger or maybe a lynx, but it had a beak, and it had a thick tail that swished in annoyance. It was a cat... with a thick sheath, and massive testicles, a huge butt and big breasts on its feral chest. 
"Aren't you a pretty kitty?" Toby asked.
The creature turned toward him, and then started walking towards the boy. It was a bit smaller than him, but it was a lot bigger than any cat he'd ever seen.
"Um... nice kitty?"
The cat-like creature padded right up to him, and then stood on its hind legs, pressing against him. Its paws rested on his shoulders, and it leaned in close, sniffing at his face.
"What kind of cat are you?" Toby asked, and the creature licked his face. He laughed, and tried to push it away. "I don't think we're supposed to pet strays, are we?"
The creature let out a chirp, and rubbed against him, and he was shocked to realize it had a fat erection under that sheath, and was trying to rub against his crotch.
"Stop that!" He tried to shove it off, but the creature was stronger than him, and held onto his shoulder. He stumbled back, and fell down, and the creature immediately followed him.
"Ow..." Toby whined, and the creature climbed up onto his belly. He felt a wetness against his belly, and looked down to see a thick drooling cock pressed against him.
"Hey, no, that's..." He struggled to get out from under the cat-like creature, but the animal pinned him down, and ground its fat, slippery dick against his belly, letting out little moans and squeaks of pleasure. He felt his own sheath and balls bulging larger in his shorts, and his butt ached in new need.
"What's going on? Stop it! You're not allowed to-" the boy's voice choked off as the cat's mouth lowered down, and its rough tongue swiped across his muzzle. The taste was... sweet. Sort of like maple syrup. And it filled him with warmth, making him tingle all over. He groaned, and his tongue rolled out of his mouth, his mind getting foggy. The creature's tongue swiped his again, and Toby's whole body went limp. He panted, and his tail wagged. He didn't understand what was going on, but he was warm and happy and full of love.
"Mew..." he moaned, as the cat's tongue swiped his muzzle once more.
"Rrreow..." the creature mewed, and Toby felt its thick, sticky dick rubbing up between his thighs, sliding through the gap between his legs.
"Noooo..." Toby moaned. He wanted to tell the kitty no, but his brain wasn't working right, and his words wouldn't form.
The creature pulled its mouth back, and a string of thick drool dripped down onto Toby's chest. The creature's claws hooked into his shorts, and dragged them down, revealing his plump, tight ass, and the soft pink tip of his own dick. He whimpered, and his head turned back and forth, his paws weakly pushing at the creature's sides.