To his credit, Devero is able to force his attention to the actual task at hand, instead of just the hands alone. And the pattern is pretty simple, once he sees it repeated a few times.

"I think I've got it," he says shortly. He holds out his hands, palms up. (He also catches the corner of a lip between his teeth again, as if using the bright spot of pain to remind his libido to behave itself.) "May I?"