When book-loving Rin Ishimatsu enters high school, she stops reading in order to make friends. But she ends up serving on the library committee with Rei, whom she meets on her first day at school. One day, on the way home from school, Rin sees a kitten and is asked a strange question by Rei. 高校生になった石松りんは、友達を作るために大好きな読書…