Ruka Mikazuki

Someone who later works with Makoto and Yukiko to escape the city and the Managers. [Spoiler] It is later revealed he works with the managers in exchange to regain memories of his old life via shortcake. He is ranked one level above them as an expert. [/Spoiler] [Spoiler] He meets with Yukiko and Makoto (having retained their memories) at the end of the story from a youth detention center, implying in the "real" world he was a criminal. [/Spoiler]