Long ago, at time when Heaven and Earth were one, the world was filled with beauty and the Angels sang to the stars. However the only source of fear were those Angels that hunted humans. The humans raised the flag of rebellion and fought back, beginning the long war. In the midst of the war, Apollonius, a slaughtering Angel, met a girl named Celine and fell in love at first sight. Casting aside his wings, Apollonius joined Celine and the humans, and helped them create the mecha warriors that gave humanity a chance of winning the war. Angry at the loss of his ‘love’, the Angel Touma seduced and corrupted a human as revenge. And now some 12,000 years later, the battle is still raging. Legends tell of the dark betrayal that killed Apollonius, but they also speak of how he would return to finish the battle started so long ago.