demons angels and titans

There are three realms. One where demons live in chaos, one where angles live in peace, and one where humans live amongst themselves.
Lucifer, sadly, lost his daughter at birth and a strange demon comes claiming he knows how to bring his daughter back. But at what cost.
years have gone by and both demons and angles have gone missing. Gods say they have died and have been reborn. The mysterious demon has gone missing yet no one thinks he's been reborn.
Is the mysterious demon still working on bringing Satans child back? Are the angels and demons actually dead, are they all alive? Or is something more sinister going on?