One day, the high school student Yachi Haruaki receives a mysterious black box sent by his father from abroad. It is a "Cursed" object, which can assume human form. The black box, whose name is "Fear", came to Haruaki wanting to rid herself of the curse. Together with Haruaki and his boarder Konoha, Fear decides to do helpful things, in order to neutralize the negative energy that is built within her, to be free from the curse that binds her.