And there was another sign of surprise. Was Kuroro not supposed to notice that? But Nataku's face was fairly open, for someone so deadpan, and Kuroro was a master at observing people. He only smiled at the answer and shifted so he was on his side, facing the boy.

"It's a polite way of showing that you're concerned." That wasn't too right... but it was accurate enough, in the kind of society that most people moved in. "It shows that you're paying attention to the other person, and that you want to know how they are even if it's obvious. You also want them to know that you want to know how they are, I guess. There are varying reasons for such a thing, but yes, the most common is concern or the need to show concern."