As humans, we used to believe it was only us in the world; the top of the food chain. We were wrong.
In the prime of humanity, the veil separating us and THEM shattered; our protection gone in the blink of an eye. Angles and demons spilled into our world like wild fire, destroying everything in its wake. We were completely unprepared for the onslaught that followed, and the Great War between demons and angles began. Humanity became caught in the crossfire, leaving millions dead and only a few remaining.
With humanity on the brink of total annihilation, demons and angles entered into a pact, thus finally bringing an end to the war that lasted over a century. What little habitable land that was left, was divided equally between the two opposing sides along with the remaining souls living therein, only to be noted within this pact as "collateral damage" .
A new society was born. A society of supernatural beings taking our place as stewards of the earth; life above all. And so, slowly the charred remains of human civilization was swept away, making way for new cities to rise from their ashes.
A tense pease. For now.