Although Kokoro is dating her third-year boyfriend, she secretly loves Yuuki, who is also on the baseball team. Under these circumstances, she begins working as a manager. One summer day, after school, while Kokoro is tidying the roof alone, she is suddenly caught in a downpour. The door to the school building is locked. Forced to enter the clubroom, Kokoro unexpectedly encounters Yuuki, who is also trapped inside. In this unexpected world of two, with poor cell phone signal and unable to contact the outside world, the two huddle together in the confined space… The young couple become intimate in the uncomfortable humidity…