KURAMA (Yu Yu Hakusho)

He seems like a normal 15-year-old student who is unfortunate enough to go to Meiou High and wear their garish pink uniform, but in reality he is actually a thousand-year-old fox spirit reincarnated into a human body. To save his mother, he conspired with Hiei and Gouki to steal the three treasures of Reikai. As punishment, he joins the hero of the story, Urameshi Yuusuke, and becomes a Reikai Tantei, whose duty (as far as I can discern) is to go around beating up bad guys and take part in really violent tournaments.
Reasons to like him:
1. He's got the most beautiful eyes I've seen on an anime character!
2. His relationship with his mother is so touching...
3. He's polite, friendly, and always remains calm in any situation.
4. He's, like, the smartest person in the entire manga!