As daily life goes on unchanged, the girls - and Haruto - continue to sharpen their fangs. They are summoned for a mission of unprecedented scale, against the religious organization "TFA", where Enishi and Kuroe await. What kind of hellish scenes will Arisaka have to face on the battlefield?

As daily life goes on unchanged, the girls continue to sharpen their fangs in silence. Even Haruto seems to be preparing for an inevitable showdown, as he takes up his sword again. Echoing voices call out to them from far away. All units of SORD and CIRS are summoned for a mission of unprecedented scale. Their enemy: the religious organization "The Fatal Answer", or "TFA", where Enishi and Kuroe eagerly await a climactic confrontation. Meanwhile, Arisaka Shiori finds herself in two minds. As a teacher and staff member, and as a human being, should she allow her students to jump headfirst into this battle, or should she forbid it? Their fate lies entirely in her hands...