Tatsumi Sekiguchi reads part of a transcript, titled "The Woman inside the Box" by Shunkō Kubo; and imagines himself as the story's protagonist. In it, he is traveling to his grandmother's funeral on a train with another man, who possessed a box containing the live head of a girl. In the main storyline, Kanako Yuzuki chooses classmate Yoriko Kusumoto to be her friend. Yoriko's mother, Kimie, believes Yoriko has been influenced by a mōryō, an evil spirit, when Yoriko begins taking nighttime strolls with Kanako. Kanako and Yoriko plan to go to Lake Sagami over summer break. On the night they leave, Yoriko witnesses Kanako crying, as well as a pimple on the back of her neck; both points perplex Yoriko. Soon after, Kanako is hit by the train on which detective Shutarō Kiba is traveling.