Altair of the Hyperbolic Plane: Beltrami Pseudosphere.Mayuri asks Suzuha to tell her everything she knows about the future and what Rintaro has been through, learning that Suzuha plans to travel back to the past later that day. Wishing to see Kyouma Hououin again despite her romantic feelings for Rintaro, Mayuri decides to go with Suzuha to the past to convince the Rintaro of the past not to give up on saving Kurisu...