A Future of Lost Memories - S2.E8

Following Hagane's attack Tomo awakes to find himself all alone in the First World with no idea of how to get back. He soon encounters the 'Witch of Rakurowa High School', a strange Daughter and very strange versions of the people he knows. However, after a chance encounter with Tokiya's sister Aki he is reunited with Takatsuki. He also learns more about the Superstring Gravity Reactor accident that started everything.