The world was once again plunged into darkness by the Amano-Iwato-Gakure that occurred about two hundred years ago.The "Three Sacred Treasures," imperative to reclaim the light, were stolen by those from Yomi, and the world was in disarray.
Time passed, and humans imbued with the power of Yomi began to be born in this world.The people who gained Yomi's power rebelled to reclaim the "Three Sacred Treasures."
*Amano-Iwato-Gakure - the hiding of Amaterasu Omikami, the sun goddess, in the heavenly rock cave *Yomi - the Land of the Dead / the World of Darkness