A residential building stands on the outskirts of town. A college girl named Rin has moved into one of the room in the building. One night, she sees a huge insect coming out of the arm of a woman. She goes to a library, and learnes that they are called “Spirit Bugs”, and have existed since ancient times. Rin attempts to unravel the mystery of the Spirit Bugs, but this is only the prelude to a new form of terror…..