Yuna's father sent Dr. Akai some vials containing potions that might help Kazuki increase his magic count. Yuna ended up inadvertently releasing a pathogen from the vials that takes on her form but completely opposite personality. While Yuna goes around thinking of ways to save Kazuki, Dark Yuna wreaks havoc in the school.
夕菜の父・健太郎から、”魔法が増えちゃうかもしれないお薬”が紅尉の元に送られてきた。夕菜はその薬を保健室に取りに行くが、何故か瓶の中身は空っぽだった・・・。
夕菜の戻りが遅いのを心配した和樹達は保健室に様子を見に行くが、入れ替わりに教室に戻ってきた夕菜は別人のような性格で・・・？
