Give me a Slow Death [Destiel]

Dean clenched his teeth in pain. "What the hell was that for, Cas?"

Castiel tipped his head and squinted his eyes. "I apologize. I had believed that these were actions that brought sexual arousal to your kind. I have been mistaken."

Dean's eyes widened and he looked down. "I mean, I'm kinda semi-hard. Could you do that again, but in a less... life-threatening way?"

Castiel smirked. "It would be my pleasure, Dean."