a postapocalyptic fantasy notion

I once read somewhere that there's some bible quote about the meek inheriting the Earth, and also that this is supposed to be wildly taken out of context, as it was originally placed as what comes next after people choose between Heaven and Hell during Armageddon. And I got to thinking... If God's done with the world, why would there still be an Earth for them to inherit?

The obvious answer is that the Earth would hang around so that they would have a place to spend the rest of their miserable existences. But, if God's crossed the whole Earth project off his to-do list, what's to keep the legions of Hell from setting up shop?

That's the core idea of the setting. Armageddon happened, the righteous got yoinked upstairs, the wicked got flumped downstairs, and the lazy ass stupid masses remaining got abandoned from above and invaded from below. With Heaven not caring any more, there was nothing to keep the demons from turning the world of the meek into a playground. Mayhem, slaughter, rape, and other vile antics would be commonplace, and lots of less than voluntary demon-human crossbreeding would result. (Bear in mind that the invaders are extradimensional entities who call Hell their home, so there's not a whole lot of ethics for them to worry about.)

This brings us to the topic of an anti-Christ, which theoretically is supposed to be key to Hell's battle plan in their war against Heaven. However, no such animal showed up during Armageddon (later known as the second war against Heaven), giving rise to the popular belief among the demons on Earth that when they do get an anti-Christ, it'll be to lead the way for their third war against Heaven (thus all the crossbreeding).

A few centuries go by, and they seem to have run out of humans. So the full-blooded demons (and a rare fraction of the hybrids with the right powers) go back to Hell for whatever's going on there, while the vast majority of the many various and sundry hybrids lack the ability to travel between worlds. So the world's remaining population are all demonic hybrids, and it's a nasty brutal place.

However, the world hasn't been destroyed yet, so there must be at least one of the meek remaining. In the first arc of the story, that survivor is discovered, most likely in cryogenic suspension of some sort. And it's a woman, thus giving the anti-Christ hopefuls a goal.

Her main ally would be a demonic hybrid of a more practical sort, who believes that "third time's the charm" is a bad plan for picking a fight with Heaven. Plus, he's got no cause to believe that he'll be rescued when the Earth eventually gets destroyed, so keeping her alive (and neither pregnant nor running screaming into the night for somebody else to then go kill her) is in his best interests.

And as they say, wackiness shall inevitably ensue...