Sebastian nods a little; he does in fact know this already. People need sleep to restore energy. Some - like a number of demons he knows - just do it because they find it pleasant. Sebastian doesn't understand that mindset at all, but different strokes... Typically he likes hearing about the likes and dislikes of mortals (makes it easier to understand them), but at the moment he's not so much in the mood.
"Certainly the depletion of energy this past week has been utterly disproportional, however?" That's what he wants to know - does napping actually do any good now, while the world's magic is acting up?