Review Detail of sataneal in Highschool DxD: Findings

Don't try this the author doesn't even attempt to make this different he joins Rias's peerage because the author wanted him to even and the reason the author gave is that he wanted to the mc to absorb the energy within the evil pieces so that his body can produce it but still continues to be Rias's slave even though he has no working evil pieces within him cause they are out of energy