[...Wow, he really was taking this seriously. Granted, if he didn't take it seriously at all, she would criticize that, too, but this is half just teasing. That he's trying this hard is really kind of cute and funny.

It takes her a moment to reply, trying to cover her amusement as best she can. It's not entirely successful, but she put the effort in.]

You really are a serious guy, aren't you? Maybe a little too serious. [A deliberate beat pause.] But if you're going to be too serious about something, this is a good thing to pick.

[She nods firmly.] All right. I'll keep watching you, and maybe a little of the whatever, but as first impressions go, you're doing a good job.