For thousands of years, Heaven and Hell have been trapped in a vicious cycle of war. The Celestial Realm floats high above the skies, untouched by mortal suffering and ruled by the Angel King, Seraph — a divine ruler feared for his ruthless discipline, terrifying strength, and absolute control over Heaven. Beneath the world lies the Infernal Kingdom, a realm of fire, pleasure, and violence ruled by the Demon King: Luceris, the First Sin himself.