If the mashup doesn't work, I have a backup plan as well. This one is also more fleshed out... See, there was a war going on where the humans don't know it against demons and angels. Several demon human hybrids and angel human hybrids were born in the midst of this war, and, upon their coming of age, discovered their powers. Now they have to work together in order to stop another war from starting, this time threatening to engulf the human world in it's chaos.