死者の供述 (Shisya no kouzyutsu)

Six men and women participated in a certain hot spring tour. Just an unusual tour held in a slightly unusual place, It seemed that all the unusual people gathered together. But the hot springs were great and the view from there was exceptional. The next morning, one of the tourists, "Kirifuri" is found dead. He died from a fall from a cliff. Dead men have no mouths to feed. Accidental death or murder? The truth was supposed to be a mystery... However, one of the tourists happened to be an shaman, a person who can speak the voice of the dead. And not just one, but all of them seem to be itako. How is this possible? The investigation begins in a bewilderment.