Rintaro Natsuki is a bookish, unsocial high school student living with his grandfather, helping to run his grandfather's secondhand bookstore. When his grandfather dies, he gets even more withdrawn. An aunt he barely knows organizes the funeral, and makes plans to close down the bookstore, and take him home to live with her.
But during the week between the funeral and the day she'll come take him home, and the removal company will take away the books, some very strange events happen. The first strange events don't quite register how strange they are. Rintaro knows he doesn't have any friends at school, so he doesn't quite know what to make of it when he gets visits at the bookstore from a boy, Ryota Akiba, who wonders why he's not attending school and also wants to buy some books, and from a girl, Sayo Yuzuki, who is his class representative. She's worried about his non-attendance, and brings him his homework. It's a bit more undeniably weird when the talking cat shows up.