One of the good surprises of this season, was Yui. She is really more mysterious than the other two leads, because of her cheery personality, I didn't think there was much to her, in the first season, than her crush on naruto, which was a bit confusing (already know what ties them together with the accident, but it still feels there something off about her). She seems more aware, and not just an air head. She is hard to read, unlike Yukino and naruto, and that adds some complexity to her character.