Toshihide Yura was a prominent scientist specializing in artificial life forms at the Kiryu Biotech Research Facility. His research into Artificial and Intelligent Cellular Organisms (A.I.C.O.) inadvertently triggered the catastrophic 2035 "Burst." This event unleashed uncontrolled synthetic organisms called Matter throughout the Kurobe Gorge, causing mass casualties and a quarantine. Initially believed dead, Yura's brain was salvaged by colleague Dr. Susumu Kurose. Kurose implanted it into an artificial organism, "Duplicate One" or "Unit One," granting Yura survival in a new form. He adopted the identity of Yuya Kanzaki, a 15-year-old transfer student with black hair and grey eyes attending the same school as Burst survivor Aiko Tachibana. As Kanzaki, he projected a mature, aloof demeanor. Operating under this guise, he approached Aiko to reveal she had lost her original body during the Burst; her brain resided in an artificial body, while her original biological body, integrated with Malignant Matter at the Burst's epicenter (Primary Point), contained an artificial brain. Yura/Kanzaki guided a team of Divers, including Aiko, to Primary Point, claiming the goal was to end the Burst while maintaining an air of mystery about his motives. His true identity was uncovered during the mission, revealing his ultimate goal extended beyond stopping the Burst. He intended to perform a complex brain transfer, restoring the original Aiko's consciousness to her biological body held within the Matter while preserving the existence and consciousness of the artificial Aiko (Aico), whom he deemed equally valid. This plan marked an ethical evolution from his earlier research. His exceptional, near-"god-like" scientific expertise enabled him to devise and execute this advanced procedure under extreme duress. During the final confrontation at Primary Point, he faced opposition from Dr. Kyōsuke Isazu, who sought to manipulate the Matter to save his comatose daughter Yuzuha, even at the cost of both Aikos. Despite obstacles and imminent military bombardment, Yura successfully performed the transfer, restoring the original Aiko to her body and enabling the artificial Aiko to regenerate a new body via a backup mechanism involving her pet companion Gummi, which contained her artificial form's data blueprint. This outcome ended the Burst and preserved both Aikos as distinct individuals. Following these events, Yura ceased operations as Yuya Kanzaki.