Naruto: Orochimaru/Sasuke, feeding the snakes
Sasuke watched the huge python swallow its prey. Orochimaru stood beside him, reciting facts about snakes. He had ordered Sasuke to learn about them or he wouldn't teach him the summoning jutsu. Sasuke pretended to listen, but he had no interest in herpetology, he just wanted more power.
"I don't think you're paying attention!" Orochimaru snapped. His hand gripped the back of Sasuke's neck and he forced the boy around to face him. He glared at first and then grinned, which was so much worse. Sasuke tried not to shudder.
"You'll learn to appreciate my little hobbies, Sasuke," Orochimaru said. "I think it's time for a pop quiz."
Orochimaru shoved him against the wall, one hand already working at Sasuke's belt. Sasuke stood motionless; by now he knew better than to fight Orochimaru's advances. Cold pale fingers slipped beneath his open shirt and waistband, sending his clothes to the floor and leaving Sasuke naked in the cool air. He distantly hoped that no-one walked in on them; that had happened once before and Kabuto still glared at Sasuke whenever he saw him.
One icy hand grabbed both of Sasuke's wrists and held them up while the other hand slid down his body.
"Tell me..." Orochimaru rasped in his ear. "Are snakes endothermic or ectothermic?"
Sasuke gasped at the hand on his hardening length. Orochimaru's skin was cold now, but Sasuke knew from experience that it would warm the more he touched him.
"Ectothermic," Sasuke said, trying to keep his voice steady.
"Very good," Orochimaru said. His mouth closed over Sasuke's, tongue sliding past his lips, tasting him. Sasuke kissed back, as expected of him, and moaned when Orochimaru's thumb circled the sensitive head of his cock. Orochimaru continued making slow movements, drawing things out until he was done with his questioning.
"Now tell me something about Tiger Snakes," Orochimaru said. He saw confusion in Sasuke's eyes. "Anything," he urged. "Go on."
Sasuke searched his memory desperately for some random fact. "They're poisonous-"
Orochimaru's nails dug into the flesh of his wrists.
"What's the difference between hemotoxic and neurotoxic venom?" Orochimaru's fingers teased Sasuke's erection while he waited for an answer.
Oh, God, Sasuke thought. It was like an educational snake exhibit gone horribly, horribly wrong. He bit his lip. He was already close to the edge and he wanted to come and be done with it. "Hemotoxic venom… affects the circulatory system. Neurotoxic venom affects the nervous system." He hoped that was right.
"Good," Orochimaru said, sounding genuinely pleased. He released Sasuke's arms and knelt down, taking the boy's length into his mouth. Sasuke gripped the material of Orochimaru's shirt at the shoulder, not daring to grab hold of the man's hair, and choked back the desperate noises trying to escape his throat. He finished in moments and slid to the floor, trembling slightly, eyes half-lidded. Orochimaru demanded one more kiss from him before he stood up.
"I think you're almost ready to learn that jutsu," he said as he walked away.
Sasuke let out a shaky breath, gathered up his clothing, and headed for the showers.