You Takami

A kleptomaniac and an informant to Assistant Warden Tamaki, You was hired to watch over Ganta in return for large amounts of Cast Points. Though apparently friendly and polite, in truth he is ruthless, scheming and somewhat paranoid, given his position as a spy for the prison's staff. A rarity among the prison population, You got himself captured and sent to Deadman Wonderland in hopes to find his sister Minatsuki and buy her freedom with the accumulated Cast Points he got from Tamaki. He cares deeply about her, so much so that he is often thought of suffering from a sister complex, much to Minatsuki's disgust. The two eventually manage to forge an estranged relationship.

(Source: Wikipedia)