Demons and Angels have always fought each other, ever since the first sun rose up, they have sought to kill one another. In every single history book, they will be mentioned shedding the opposites blood. It is inevitable.
And as long as anyone can remember, humans have been caught in between. The acts of war have always taken place on earth, as it's placed between heaven and hell, and always have the humans had the biggest number of casualties. But they're not innocent; no they've always chosen sides. Whether they have been with the Demons or the Angels. Alliances only lasts until the end of the war. And the wars can only be won by one person. A person always named in the history books at the end of each war.
The Champion.