Lavi is a character from the anime/manga series D. Gray-Man. In this series, Lavi is a "neutral" Bookman in Training who is tasked with recording the events of the secret Holy War. While those in the Bookman Clan are neutral in order to record history through unbiased eyes, he along with his mentor, Bookman, help the exorcists (the good guys) fight against the Millennium Earl and the members of the Noah Clan (bad guys).

I for one love Lavi and the role that he plays in the series. He comes off as a huge flirt, energetic, and resembles a bunny as Kanda -another character- refers to him as. But then on the other side of the coin, there is so much that we don't know about him. :D