Yu Yu Hakusho-1
The universe of Yu Yu Hakusho focuses on three primary worlds. Earth, the human world. Makai, the world of a variety of supernatural beings known as youkai. And the Spirit World, a place where humans go to be judged after they die, and whose natives keep the balance and order between these three worlds.
This theme differs from canon in that Yusuke didn't die at the point of the original timeline, which allowed the Artifacts of Darkness to be stolen from the Spirit World and never returned. As a result, King Enma, the ruler of the Spirit World, is pushing particularly hard to re-assert his authority. Anyone breaking the laws of the Spirit World, no matter what world they're in, are hunted and harshly punished. The Three Kings of Makai still rule their territory untouched, but anything outside of that territory without a proper ruler has become fair game for the soldiers of Spirit World to slaughter as fugitives.
As far as Earth goes, it's simply caught in the middle of the chaos. Most humans have no idea what goes on. But those with spiritual sensitivity are still caught up in the skirmishes, or are even fugitives themselves. Low powered youkai try to make a name for themselves in the human world, or find some peaceful area to hide away from everything.
Who knows where exactly this new timeline will continue to branch!