The original school supernatural fantasy light novel series centers around Harutora, a boy from a branch of the Tsuchimikado family of onmyōdō occult practitioners. However, he lacks the ability to see spirit energy, so he is now just an ordinary high school student. Natsume, a girl who was Harutora's childhood friend and the next head of the Tsuchimikado family, reunites with Harutora and changes his future.