The world is overrun with monsters called Nemeses—and a young boy infected by one will stop at nothing to defeat them all!

Evil creatures called Nemeses fall from the skies and the only ones who can fight them are Wizards—infected ones who survived a Nemesis's corruption. Seth, one of these survivors, vows not only to fight the Nemeses, but to find their mythical nest, Radiant, and destroy it!

Seth finds himself face-to-face with a man named Piodon, who claims to be his brother. Picodon came to Rumble Town to watch the destruction, but upon finding Seth, offers him something to help with his infection. Meanwhile, Grimm and Mélie continue trying to prevent Hameline from destroying the city.