On a winter night at a junior high school, Koharu Fujino, a girl who died 40 years ago, quietly returns students’ lost belongings to their owners. One evening, Aoi Morikawa comes back to school in search of her forgotten scarf and sees Koharu. She soon learns about Koharu’s past and the locket she has searched for for years—a keepsake from her mother. Now, Aoi returns a “lost item” to the girl who has spent so long returning everyone else’s. A bittersweet yet heartwarming animated trailer set in