I'm not necessarily opposed to it, but it might be difficult to justify as I don't play him all that friendly or particularly outgoing (more insufferably arrogant and self-involved). He does like pretty girls, however, tending to make more of an effort to be on good terms with him (though it's largely to get them to do things for him) and Cho's being older than his year as well as being very attractive would make her more interesting to him. I guess what I'm saying is I can see why he'd be nice to her, but not really why she'd bother with him... unless she just makes a habit of befriending younger, good-looking men.