As the summer break draws to a close, the girls squeeze every last moment into fun. Their carefree antics are interrupted when Suguru Koshigaya clinches a lottery jackpot—tickets to Okinawa! Rushing into packing, the Asahigaoka crew sets off for a three‑day escape to finish their summer. They laugh, chase each other through the streets, and savor every sunset.
On arrival in Okinawa, they check into a ryokan where they meet Aoi Niizato, the hostess"s daughter. Though close in age, her composed air makes Natsumi Koshigaya ponder her own youthful impulses. The inn"s gardens and the scent of fresh sea air greet them. With a budding friendship on the horizon, the girls dive straight into ambitious sightseeing and local adventures!