The Banten shinobi and Grey Wolves are under attack by the students at Alya Academy. Raimei tries to talk Subaru out of fighting but Subaru reveals she wants to use young brains to make the forbidden cure-all Daya, which she wants to use to cure the headmaster, who is dying. Raimei, Juuji and Miharu are captured but the others can't get into the basement where the other kids are until Kannuki shows up, capturing Kouichi and forcing the others to surrender. The fighting starts again and Kouichi gets shot. In the basement, Miharu's tries to help Yoite and prevent him from dying but unleashes the Shinra Banshou. Kumohira attacks and stops him but then Tasuku locks everyone in the basement where there is no air. He goes to get the Daya scroll from the headmaster revealing he's been working for government the whole time. Kouichi shows up, revealing that he can't die and Tasuku kills himself so as not to be killed. Kouichi and the headmaster let everyone out of the basement and the headmaster finally dies. Shijima gives the Daya scroll to Miharu and in a conversation with Kouichi, she reveals that she is actually Miharu's cat Shiratama.
Yuhki Kamatani's debut work, NABARI NO OU, was a finalist in the 2005 Japan Media Arts Festival in the "Story Manga" category. The series' popularity later led to its popular anime adaptation.