illyisabot
Let him have knowledge of DxD. Would be good for his planning and knowing what power level he needs to reach. And change the plot according to his own will. For example, if he knew god is dead, go and take boosted gear and give it to your own strongest grim reaper. Go and take samael for yourself. Take Lilith for yourself and create super devil army early. Make a deal with the god of the Bible so that you are responsible for all souls in the afterlife or somethingy