In 1995, all 800 habitants of the isolated Kamikakushi Island vanished in one night, all but a single girl who lost her memory. The cause of the disappearances was never identified. Four years later, that girl, Mari, transfers to a girl`s dormitory school, Kaihou Gakuen, leaving behind her grandmother who had been her guardian ever since the incident. There, she meets Hagino. Hagino is the school idol and completes her student council responsibilities flawlessly. The moment she touches Mari