Since ancient times, demons, ghosts, and humans have lived together in this world. However, with the advancement of civilization, human beings' "vision" has become increasingly narrow. Ignoring the reality of this world, they blindly and arrogantly deny everything that is "non-human". Even if they exist around them. In order to maintain the subtle relationship between humans and "non-humans", those ancient families that inherit mysterious power have produced such people, powerful people with clear "vision". In the supernatural industry, they are called - spirit hunters.