As the oil touches Benedict's hand, he begins to spread it around over his fingers, as one does, in a motion that's more automatic than intentional. He pauses when Colin speaks, and although he looks slightly surprised by the request, he nods silently, glancing him over and then beginning to blush.
This is farther than he's ever gone. "I, ah..." he begins, and murmurs, "...will you tell me how?"