Misawa Cram School (Science Cult).Tōma continues to keep his memory loss a secret and inadvertently upsets Index when he meets with his two friends, Motoharu Tsuchimikado and Pierce Aogami, who both inadvertently insult her. Forced to buy them all lunch, they go to a fast food restaurant, where Index gets into an argument with a girl dressed like a miko, who says that she is a magician and leaves before Index can get any answers concerning which magical organization the girl belongs to. On the way home, Index chases after a kitten she names Sphinx and is separated from Tōma. She then runs into Stiyl, who needs Tōma to rescue Aisa Himegami, a girl codenamed "Deep Blood", from Aureolus Izzard, an alchemist leading a secret science-worshiping cult at the Misawa Cram School after three years in hiding. When Tōma refuses, Stiyl coerces him with threats that Necessarius will take Index away. When they arrive at the cram school, Tōma is surprised to learn that "Deep Blood" is the girl he met earlier and finds a dead corpse in a suit of armor.