Yuki Sakurai, an orphan who has always been able to sense other people's emotions with a touch, is pulled from his quiet life at fifteen when a silver-eyed man named Zess saves him and stirs a strange sense of familiarity. Soon after, Takashiro Giou arrives claiming to be Yuki's older brother and invites him into the Giou Clan, a family whose members carry inherited powers used to fight duras, demonic beings that threaten the human world. Yuki has to decide whether to accept a past and a family he never knew he had.