Robin Sena arrives in Japan to replace a fallen member of the STN-J. Engrossed in a witch hunt, the members of the team are unaware that this quiet 15-year-old is the new Hunter and brush her off. When they finally corner the Witch will they come to appreciate Robin's power?

Robin and Amon finally confront Zaizen and learn the truth about Robin's existence. To Zaizen's surprise, instead of being traumatized, Robin is instead strengthened with resolve. Now Robin and Amon must stop Zainzen's final solution for the sake of both Witches and Humans alike.