Rui Kamishiro is a good-natured genius. He carefully makes each show the best it can be, using his flair for technology and ingenuity. And at one of these shows, one of his equipment malfunctioned and was supposed to fall on Tsukasa, but Rui pushed him away in time and took the blow on himself, from which he died almost immediately. And about a month later, in the form of a dead spirit, he appears to Tsukasa to say that it is not his fault.