Kou had been hunting down the third school mystery, the hell of mirrors. By luck, he had managed to find himself in the hell of mirrors boundary, now he only had to find the spirit who controlled it and to exorcise them.

While he wandered around, he spotted a familiar pink haired boy crying while being tormented by a dangerous spirit, Tsukasa, whom he had encountered before. He soon realised the familiar boy was his old ghost friend Mitsuba, whom he had watched disappear in his arms. He thought that Mitsuba was gone for good so it surprised him, it was already surprising to see others in the boundary aswell.