A former SWAT team sniper who was forced to retire after accidentally killing a civilian during a mission. He has a withdrawn and cold personality and believes in "blood debt must be paid with blood." He was recalled to investigate the serial murder case and found that the deceased were all related to his mission back then. His right arm still has an unhealed bullet wound from that year, and he draws bloody handprints on the wall with blood every night, which is the only signal that can awaken the memory of the real murderer. His existence is the trigger of the entire case and the key to uncovering the shady secrets of the police.
