, the , is the fourth member of the team and a user, a student alongside Rio and Miki. He is also Retsu's protective older brother. After their parents died, they were taken in by a church. Gou forced Retsu to promise never to take on the Jūken, then went to face Rio. Gou used an imperfect form of the forbidden Geki Waza in an attempt to defeat and seal Rio, but it failed and Gou wandered for fifteen years in a werewolf form that he could not control.