“And if Kōjin was murdered on the first floor of the annex and cut into pieces there, only one person could have done it: Masaki Shingo. And that means that the cut-up body found later that night did not belong to Masaki Shingo, but to Kōjin. At this stage, it is easy to imagine how the body was swapped. “That night Masaki Shingo killed Kōjin after he returned to room 5. He undressed him, carried him to the bathroom and, using the meat cleaver and hatchet he had got ready beforehand, he cut the body into six parts.”