In hopes of gaining strength, Chihiro would later ask Mondo to train with him, revealing that he was male and wanting to change from being weak to strong. Mondo, feeling jealous of Chihiro's inner strength in comparison to his own, killed him in a blind rage, with the use of a dumbbell. Byakuya knew all along that Mondo was the killer, having witnessed his actions the night prior, and tampered with the crime scene to make the case more interesting. And also revealed that Toko was Genocide Jack.