Shiki Mikaido

One of the sole survivors of Hogougumi. During the battle between Garyukai and Hogougumi, he was seen as a child hidden inside a box, found by a member of Garyukai. Shiki has a deep hatred for Wakasa because he believes that she had abandoned him and the gumi. He is the only son of Sou and the omote no seisai, making him Tsukasa's biological half brother - even if he says he hates her, they truly act like siblings. He shows up when he harasses a woman into taking drugs and gets a major beating from Tsukasa who happened to be passing by at the time. [Source: Wikipedia]