白猫プロジェクト ゼロ・クロニクル

In an age long, long ago, the White Kingdom in the sky and the Black Kingdom on the earth maintained "balance" while simultaneously undergoing "cycle." One day, in a village of the Black Kingdom destroyed by a monster attack, a young boy was digging graves. Before that boy appeared the former Dark King candidate, Siskas. Discovered by Siskas, the boy resolved to become the Black Prince and change this world. On the other hand, the Light King Alice, guardian deity of the White Kingdom, worried about the balance between light and darkness being disrupted. Upon receiving news of the emergence of Baal, who threatened to destroy the balance, the Dark King proposed an alliance to subjugate the troublesome Baal. The Light King Alice met the envoy and prince of the Dark Kingdom, and the two "promised" to build a peaceful world together. However, their "promise" was trampled upon by the Dark King. The "promise" exchanged between the two and the sin that began the world's destruction—the story leading to the "origin," "ZERO," now begins—