Kae has been taken away and Kawaki must face a dangerous assassin. Himawari acts as his partner and provides support during the battle. They try to corner the enemy with coordinated attacks, but the enemy proves to be powerful. Meanwhile, their classmates, who had entrusted Kawaki and Himawari to directly confront the assassin, take action in a desire to try to help. Will Kawaki be able to save his precious friends and accomplish his mission?

But since it's come to this,
I'm not dying alone!
!لكن بما أن الأمر آل إلى هذا، لن أموت لوحدي
Allerdings werde ich sicher
nicht alleine sterben!
Pero ¡no moriré yo sola!
Pero ¡no moriré yo sola!
Ma in questa situazione non morirò da sola!
Mas como é assim,
não vou morrer sozinha.
Но раз так —
 одна я умирать не собираюсь!