Strike the Blood Novel Volume 21 is written by Gakuto Mikumo with illustrations by Manyako.
Kojou has finally defeated the Blood, but with Ren abducting Avrora and fleeing to another world, there’s no time to celebrate. And with Kojou’s vampiric powers gone, staging a rescue seems impossible…until the First Primogenitor, Ki Juranbarada, shows up with a striking proposal and a tempting offer—a new set of Beast Vessels. But when Juranbarada’s gift transforms Kojou into a monster devoid of reason, it’s up to Yukina and company to find a way to save him before it’s too late!