The kid finds himself speechless, and just watches, eyes round. Why anyone would want to hug this obnoxious guy is beyond him, which is why he's glad it's not him doing it and the Doctor making an idiot of himself. He knew that guy was a bit too weird.

It takes sometime, but after the Doctor gets shoved away, Setsuna manages to ask the Doctor, "You know him? And why did you hug him?"