Sirius was lonely. He had been living in the cave, eating only rats, for a month now. Oh, how he longed for he warmth of a woman, her soft hands caressing him. His thoughts wandered, but he was jolted to reality when Buckbeak nudged his shoulder. Sirius petted Buckbeak's feathery head as he grazed Sirius's shoulder. Buckbeak was such a loyal friend and companion. The feathers felt warm against his shoulder.
Why wait for a woman? Sirius thought. Buckbeak was right there, and he was willing, Sirius realized. Buckbeak appeared to be in heat.
Buckbeak's falcon-like eyes pierced through Sirius's being, his soul. They both acknowledged that they wanted each other. Suddenly, Buckbeak nipped the button off of Sirius's trousers, and the trousers fell to the floor, leaving Sirius exposed to Buckbeak's appraising gaze. The wild bird seemed pleased. The giant feathered creature approached Sirius and began to nibble at this cock. Sirius groaned with pleasure. Sirius began to gently massage Buckbeak's neck, as Buckbeak let out a sensual squawk. Buckbeak's tongue began to swirl gently around the head of Sirius's manhood. Buckbeak pulled his penis sharply and Sirius let out a shark cry of pain and pleasure. Suddenly, the griffin removed his beak. Sirius stepped back, unsure of the next move. Buckbeak gently moved around Sirius's back and fluttered a wing around his anus.
"Oh, Buckbeak…" Sirius moaned with delight. "Continue my friend."
But Buckbeak stopped. Buckbeak suddenly shoved his horned beak up Sirius's man opening. He thrust his beak in and out, hitting Sirius's prostate every time, until Sirius came with an "ahhhh," all over the cave floor.
Sirius had hardly finished his orgasm before he realized that he wanted to return the favor to Buckbeak. Sirius got on his knees and gently made his way through the forest of feathers to find Buckbeak's birdhood. Sirius's erection was already protruding again at the sight. The bird cooed with delight as Sirius placed his lips, hardened from years in Azkaban, on the bird's penis. Sirius's stubble from many days of seclusion rubbed Buckbeak's legs, adding to the pleasure. As Sirius sucked harder, the bird came into his mouth with a feathery shudder. Sirius swallowed the bird's salty, yet tasty, fluids, forcing him past the edge yet again.
Both completely satisfied, they nestle together, ready to face the hardship of isolation together.