Genya is Sanemi's younger brother and only living sibling. After a Demon attack befell their family, Sanemi and Genya were the only ones who survived the incident. However, after being branded a "murderer" by Genya, their relationship began to worsen and decline until the two split and went their own ways. It is revealed during the battle with Kokushibo that despite the whole incident, Sanemi still heavily cared for his younger brother and actually wanted him to live a normal life.