Devil

Devils are the most prominent beings in High School DxD, as well as being one of the most powerful. They come from Hell.

Ranks/Info
High-class Devils (Pure Devils) rule over other demons depending on their family's rank and prowess, and can have up to 15 'slaves', which are represented by each piece in a chess game (Rook, Knight, Pawn, etc.). The High-class demon takes the position of 'King'. Lower-class demons are often looked down on and usually serve a demon in higher authority. If a demon were to divert away from his/her master, they have to be killed before they go out of control.

High-class demons also have the ability to turn a human into a demon when they die, as seen with what Rias did with Issei. Also, they can't go near/get involved with anything that has to do with God, as they can suffer nasty side effects (headaches, immense pain, etc.). As seen when Issei couldn't go near the church when he was talking to Asia, or when he tried to pray but only ended up collapsing from the pain soon after.

The Devils are split into 4 ranks, they are: the Ultimate-class Devils, High-class Devils, Middle-class Devils and Low-class devils.