Elletear's attack, nothing is certain about the war between the Empire and the Sovereignty. Mizerhyby and the Hydra are rushing to beat Elletear to the center of the world in service of their ambitions. Meanwhile, Kissing surrenders to Iska to avenge her uncle, and the two join forces with Alice's entourage in order to travel to the forbidden land of Katalisk. There, they learn the truth of the astral swords, the monstrosity lurking in the planet's core, and the terrible future that awaits...