His skin is devoid of normal color, just a dark grey except for the deep red skin around his eye sockets. Horns grow from the top of his head and curve down the sides around his bearded face. That beard is black and the hairs are bristly and wiry. There is a malicious gleam in his eyes.
Many who see this creature for the first time are afraid, but perhaps not for the reasons they should be. He's a large, brutish man and with dusky grey skin and prominent horns on his head he is clearly some sort of fiend. But being physically imposing and threatening is so often one of the least dangerous qualities of a demon. He doesn't sustain himself the same way mortal creatures do, ne needs to feed off of emotion. Fear, vulnerability, helplessness and other terrible things. And of course carnal pleasure.
He uses women for all variety of sexual acts but it is hard to say whether or not he 'enjoys' it in the same way normal people do. It is hard to say if he enjoys things or feels things in any normal capacity. But what is apparent is his urgent need to satiate himself in this way, as he feeds off of emotions. This seems to sustain him, but also fuels the fiendish magic that he practices.

He can transmute his own form, as well as that of others
He can summon dark tenticles of fiendish nature that can be used to bind or even pleasure those he draws his sustenance from
He can increase the amount and potency of seed

And possibly many other things not listed.