Ep. 4: Flashback reveals Takamasa and Itsuki's past as a team and Tomoharu's transformation into a Shikabane.

4

A flashback details how Takamasa and Itsuki formed their team approximately four years ago following a bus accident that turned Itsuki into a Shikabane Hime. The pair initially struggled against a werewolf-like Shikabane but eventually defeated it. Although they grew closer, Takamasa remembered he must not treat Itsuki as a normal human. Itsuki transferred to school with Takamasa and befriended classmate Tomoharu Kishibe, who knew of Takamasa's feelings. When Tomoharu’s family was killed by a reckless driver, it was revealed he had become a Shikabane four years ago to cause such accidents. Unable to let Itsuki kill Tomoharu, she transformed into a Shikabane and accidentally wounded Takamasa before reverting. Having learned from this past trauma, Takamasa now allows Itsuki to shoot Tomoharu without hesitation.