I'm looking for something where the main character is a guy, and he starts out warm and is childish during his early years, but then there's a skip to years later, and the same warm child has grown dark and mysterious. Also, it'd be great if there was an opposite girl for the guy that notices the change.
BERSERK SPOILER
Spoiler (highlight to view)
For example, Gatsu from Berserk before he gets raped and after. There is a big change over his character.