The arise of Utopia three planes merged into one. Hell, Heaven and our reality. The demons stand toe to toe with the angels. An everlasting war. There's ton's of wasteland, ton's of survivor's who have made themselves small shanty towns under untouched highway bridges, or catacomb's. Underground sections of collapsed city where they live in hiding. There's also Oni running around among all the chaos, mostly around human's as that's what they eat.

So get out there and establish humanity another place to stand. Kill the enemy, push them back. Anything's better then nothing.

There is no city. All cities have been destroyed in this.