Nanashi from Marchen Awaken Romance...!
he's the leader of a group of thief...
and to top it off, he's x-tremely cute!!!
he's kinda a womanizer but I like him!
^_^
Shadow Lady hasn't actually become an anime, but she's my favorite Japanese thief and it's the manga I'd most like to see become an anime. She's created by the same guy who made DNA^2. When she applies special demonic magical makeup, she turns into a thief, dressed in one of several costumes, each which gives her a different ability.
