A new ethics teacher, Toga Yagari, arrives at Cross Academy. His looks, which are atypical for a teacher, are all the buzz among the Day Class students, and even Zero seems to have lost his usual composure.

Zero tried to sink his fangs into Yuki, but he was able to get hold of himself just before he succumbed to his urge. However, there is someone who is trying to kill him: the new teacher Yagari...

Yuki makes a secret decision regarding Zero, who is now determined to fight his affliction until the very end. Yuki feels guilty for betraying Kaname and keeping a secret from him...