The war between angels and demons is not unlike the war between humans. Not every soldier believes in the cause. Thousands of years ago many of these solders chose to fall to earth to live out their existence as mortals. But none of them could have expected what happened when they mixed their blood with ours. Every few generations, an offspring is born a little different. Half Angel or half Demon with immortality and untold powers, but only if they are willing to pay the price, their life. To live forever they have to die.