One winter, right at your school, a student just died, it is thought that the student died by committing suicide by throwing himself from the rooftop. But was it really a suicide? A few months later, five tall men visited your school. You don't know who the five men were and what their purpose was. But what is certain is that one of the men with long silver-white hair entered your class and called the students one by one. Now it's your turn, you come forward and sit down in front of him, he looks at you with a serious and empty look, what happened?!