Honnouji Academy's one-of-a-kind high school, which had experienced peace, was due to be closed in a month as it had served its intended purpose. However, before the school could be shut down, one final event had to take place—the graduation ceremony. As the student council members bid farewell to their past and set out to pursue their futures, Satsuki Kiryuuin, relieved after obtaining victory, struggled to find her path, making it difficult to give a speech to the students. Just as Satsuki was poised to take the stage, the ceremony was plunged into pandemonium by mysterious troublemakers resembling the student council members. Ryuuko Matoi and the Elite Four braced themselves for another fight, only to find out that an old enemy was behind the chaos, forcing them to seek vengeance.