Hundreds of years ago, when there was an evil that could not be covered by the laws of the human world, there was a family that judged sinners with psychic powers as a spokesperson for those who died as victims. People call him the "Judge of Darkness". The main character, Ichiro Ai, who is a descendant of a family of spirit mediums , takes the place of the spirits who can't float, and avenges the evil that can't be judged as a dark judicial officer.