Despite her gyaru appearance, Serina Nekozuka is a serious and hard-working third-year high school student. She is trying her best to get first place in her grade to qualify for the scholarship she is aiming for, but she has been stuck in second place for years because Reiko Tachibana, the public morals officer she hates who always blames her for her flamboyant clothes, always gets first place. One day, on her way home, she sees Reiko having an affair with an unknown woman...