The ambition of the magicians led them to awaken something they shouldn't awaken in order to gain stronger power, and the destruction of the world is imminent. Only the strongest magician princess, Kaze Susobe (voiced by Miyuki Sawashiro) can prevent all this from happening, but Kaze Susobe, who was plotted by her subordinate, Sasuke Samon (voiced by Rikiya Koyama), is trapped on an uninhabited island with a barrier. Fuwa Aika (voiced by Kana Hanazawa), the sister of Fuwa Mahiro (voiced by Toyonaga Toshiyuki), a friend of high school sophomore Takigawa Yoshino (voiced by Koki Uchiyama), was killed by a burglar, but Mahiro believes that there are many doubts about his sister's death. In order to investigate the cause of his sister's death, Mahiro made a secret deal with Kaze Susobe through a drifting doll on the sea. A month after his disappearance, Mahiro suddenly fell from the sky on a snowy winter day with butterflies all over the sky. At the same time, the terrible "Black Iron Disease" spread throughout Japan. What kind of contract did Mahiro make with the magician princess, and what mission did he bring to this world?