Astral power, harnessed by astral mages, courses through the world, but those who possess this feared ability are hunted by the oppressive "Empire." In response, the tormented mages establish the Nebulis Sovereignty, sparking a century-long conflict between the two nations. Having aided a convicted witch, skilled knight Iska is imprisoned. A year later, he is unexpectedly released on the condition that he tracks down the terrifying "Ice Calamity Witch," hoping to end the war. Similarly, the witch herself, Aliceliese "Alice" Lou Nebulis XI, seeks peace and is willing to take on the Empire. As Iska and Alice each strive for a world free of suffering, their destinies intertwine, forging a bond that transcends mere coincidence.