Due to her family's size and financial situation, Mao Uchida hides the fact that she's a girl to enter an all-boys boarding school and have her schooling fees waived. Her roommate, Yota Enomoto, is a rebellious guy who brings a girl into their room immediately after they start school! After sneaking up on Mao in the shared shower room, Yota finds out Mao's a girl. In the blink of an eye, her fate at an all-boys boarding school is in Yota's hands!