Grace from Hell

No one expected their arrival. No... That's not true. Their arrival was inevitable. But no one expected they would betray us. Children of light, the ones that were supposed to guide us towards the right path, they themselves were the ones to bring true evil onto this Earth. So what does humanity do when angels come to kill them? They turn to demons.
Christophe Hughes is soon about to become a purifier, embarking on the journey of saving innocent souls from the wrath of angels with the help of a demon. But he soon has to realize that not everything is as simple as it seems. He knows too little in a world where knowledge is necessary for survival. Too many questions emerge and none of them are answered. Why was it this demon that chose him? What exactly are angels? Why did they attack in the first place? What lies beyond the world of humans?

Just who is the Prince?