Kyosuke is an ordinary uni student. He really wants to get a girlfriend, but he is wimpy.... One day, he receives a letter from Natsumi, his classmate. He goes to a classroom at night as indicated in her letter. Soon after he arrives there, he is forced to be served as a ritual sacrifice. He is surprised to know that Natsumi is a member of an occult magic club. But their ritual fails, and his sexual energy disappears.... On the next day, he doesn't get erection as expected. Natsumi and other members promise to help him get his sexual energy back. And their summer holiday starts....
