The smile doesn't get returned, but that's unlikely to be much of a shock. Akutagawa's face seems incapable of anything but the most sadistic of grins.

What Chuuya does get is a look of mild confusion. "Be... friendly?" Akutagawa could be polite, but friendly is something else entirely. He understands the concept, but in practice, he draws a blank every time. Even the times he has tried to be nicer to people have wound up with others saying he'd been too harsh.