Honestly, Crowley needs a moment too. First there's the pressure of Aziraphale's body in general, which is more than enough in its own right to be thrilling, and then suddenly there's more and it's hard and right there and Crowley swallows hard and doesn't move except to rest his head against the angel's. "S'okay," he says thickly. "'m not going anywhere. Take your time."

He doesn't really remember what it was like having a hard-on for the first time, it's much, much too long ago. But he can make some educated guesses.