The story follows Tomoharu Natsume, a high school student who is haunted by the ghost of his childhood friend, Misao Minakami, who died in an airplane accident three years earlier—a crash that Tomoharu himself barely survived. As he begins high school, Tomoharu decides to live on his own, moving into Meiou-tei, a dormitory, to start enjoying a carefree life. This decision is also influenced by the fact that his mother recently remarried and prefers not to have him interfering with her new life.
However, Tomoharu's life takes a sudden turn when a beautiful girl named Shuri Kurosaki shows up with a mysterious trunk, claiming that Tomoharu's brother, Naotaka Natsume, asked her to deliver it to him. The situation grows more complicated when Kanade Takatsuki, a shrine maiden, also appears, seeking the same trunk that Tomoharu now possesses. It soon becomes clear that the trunk holds secrets that could unravel the very nature of the world they live in, thrusting Tomoharu into a semi-serious action-filled adventure filled with mystery, danger, and the supernatural.
