キルラキル 特別編 -さよならをもう一度-

Set after the main series, this special, 'Goodbye Again,' gathers Ryuko Matoi, Mako, and the Elite Four at the half-demolished Honnouji Academy as the school is decommissioned. When Rei Hoomaru seizes the academy's Last Resort System and turns the whole campus into a weapon, Ryuko and Satsuki Kiryuin's allies suit up to retake it. Released as a bonus episode 25, it serves as an epilogue rather than a standalone entry point.