Renji

Renji appears in the service of Shiranui, working for the immortal onmyodo as an assassin. Using his guitar-like instrument called a "yueqin", Renji is able to command fire flies that slip into the ears of his victim and ignight, burning them to ash from the inside. Soon these assassinations gain the attention of Mao who is soon able to connect Renji with the murders. Renji soon develops a hatred of Mao when the doctor slices his arm off. It is soon restored by Mei Mitazono who also aids Renji in the cultivation of more of his fire flies. Renji also frequently visits prostitutes, though he never hires there services, instead he gives money to them and treats them with a surprising kindness. It is eventually revealed that Renji's fondness for prostitutes comes as a result of his brutal childhood where his parents would seem outwardly kind and adopt other children. Behind closed doors however they were sadistically burtal, forcing the children to prostitute themselves and steal in order to raise money for their own wasteful ends. When Renji's sister, Tsuyu, is sold into prostitution and eventually beaten to death Renji has had enough. When his parents get drunk and pass out he pours the sake all over the room and burns his home down with them inside. (Source: furinkan.com)