When he did his summoning, he explicitly did not call for one of the more human-looking, appealing succubi, but instead for one of the fiercer, monstrous female preatorians of the dark lord himself. Rippling muscles and abs, full breasts and flaming red hair.
Her grin was a perverted row of sharp teeth, saliva flowing from her mouth, her claws digging slightly into his chest. But despite all that display of wild atavism, she seemed careful not to hurt her summoner, as this mating was quite the rare occasion for her.