On her way to school, Eriko is captivated by a beautiful, idol-like girl who picks up her dropped handkerchief. That day's swimming lesson is held at the nearby Shimomura Junior High School pool, as the swimming pool is out of order. After the lesson ends safely, as Eriko and her friends are about to return to Sakijo, a student from Shimomura Junior High approaches them. It is the beautiful girl Eriko met that morning...!
Eriko and her friends Yuma and Ayano are excited about entering high school. Their excitement leads to their breaking of the rules when they toured the school before the opening ceremony. They find out their preconceptions about the all female school may not be as true as they had first thought. Despite that, Eriko and her friends are joined by new friends. They aim to get through high school life together.
