The typical "this guy is the best character in the game so I like him". And frankly, I dig his support convos. His relationship with Lowen is worth a laugh, his convo with Eliwood is heartwarming in a weird way, and his Isadora support is like the best thing ever. Pretty much the perfect kind of mentor character IMO.
I'm a huge fan of FE7!Pherae, but her convo is all pretty good. Also Isadorable
He is a pretty cool guy, but really, its pretty rare for someone who played FE7 that does not end up liking this guy
I don't really find him to be "emo" or whatever the term is. Good support convo, good unit(useless in drafts though). What's not to like?
A girl that looks like a man. Stop the press. That's awesome. Also that support convo.
If you want to be a flirt, you do it like this(or maybe, like Virion), because this one manage to be a pretty cool guy. Also special note for having a sad death quote.