Quatre isn't, exactly, startled. Surprised, certainly, but that's not the same thing. His smile widens, though, as he glances at Trowa.

After they sit, Quatre unzips his sweater again--it's warmer, in the loft of the stables, than it is outside.

"What have you been doing?" The question is sincerely curious (true), and has no basis in the fact that Quatre likes to listen to Trowa talk (...well, only some).