After three dismembered bodies were found in the sewers, the H.A traces them to Toriton. Jun Fudo was sent as an undercover agent to try and find out what had happened. On her first visit, she meets with two of her old students Mizuho Nishikawa and Chihiro Shimura as well as her old adversary Aoi Kurosaki. Later on, Lan Asuka informs Jun that Aoi was the Devil Beast who had committed the murders; and later that night Jun goes to try and talk to Aoi.
However, Aoi's demon form had already manifested. Aoi had split personalities which caused the Devil Beast to split from her, leaving Jun to briefly battle with her Devil Beast half in the water. Thereafter the H.A arrives comforting the normal part of Aoi and wait for Jun and the Devil Beast to reemerge from the water; whereupon the H.A. proceeds to unleash a barrage of bullets on Aoi's Devil Beast, killing it. The Club apparently continues on with normal business afterwards.