It all began when Teiichi finds himself lost in one of the school's old buildings, where he stumbles upon Yuuko whom introduces herself as the ghost of the school. While he tries to understand how she came to be, they decided to start the Paranormal Investigations Club. Momoe asks him to help her with a paranormal problem, later explaining she played a strange game called "hide-and-seek" which only ends if you reveal the doll you use, but the doll mysteriously disappeared and she fears she will be killed. In truth, the doll was actually taken by Yuuko, but she warns Teiichi that Momoe's paranoia will kill her if they do not solve it. In order to end her fear, Yuuko and Teiichi play pretend where the latter performs an exorcism on the possessed doll in front of Momoe.