The Black Sword Shaman I.Blue Elysium (ブルーエリジアム), a new fantasy marine resort, is holding its trial opening and Motoki wants the gang there. Kojo and Asagi end up working a yakisoba booth while Yukina and Nagisa see the sights. Elsewhere on the grounds, Sayaka rescues Yume Eguchi, a younger girl abductee but after giving the girl a photo of Kojo and sending her ahead to the lifeguard centre, is herself taken prisoner by a mysterious sword shaman. By the aquarium, Yukina encounters a schoolgirl in black who carries a case similar to Yukina's over her shoulder. When Kojo delivers drinks to the lifeguard centre, Yume follows him back to the booth and eventually to the suites where a barbecue gets underway. Yume reveals that her sister Riru was also confined and that an organization is conducting experiments for which her sister had been a willing subject. There is a connection to the ownership of the new resort. The same girl observing Yukina earlier also captured Sayaka, and held a cryptic conversation with Kazuomi Kusuki, who runs the company that Yume discussed. She identifies herself to Sayaka as a shadow of a sword shaman.