Yuka, Rinko, Saki, and Natsumi are childhood friends and classmates nearing the end of their second year of middle school and eagerly awaiting their summer break. Unfortunately, it's a bittersweet time for this close-knit group, as Saki is transferring to another school. The girls are determined to keep the spirit of their friendship alive, even if only for this summer. They reminisce about a large stone the four of...