"Servant, go find me more flesh to conquer", you command. "Yes, my missstresss", she slithers before taking on her human form again. She walks out of the door, and you return to your human form as well and get dressed. You wait in the bedroom for your next victim, and to your delight you soon hear a soft knock on the door. "Ma'am, this is the man you wanted to speak?" You eye the young man from top to toe. He looks about 20, and has no idea what's going on. "Yes, he'll do for the job. Close the door please, miss." Your servant does as you ask and you walk over to the man. "Now, you're probably wondering what this is about", you say. You slowly begin to remove his clothes, at which he stares at you in amazement and confusion. "These would only get in the way", you tell him. As soon as he's fully undressed, you plump him down on the bed, sit on top of him...and show him your true form.
In rapid succession your wings, skin, horns, fangs, claws, tongue and tail change, making the man now desperately try to get away to no avail, as your demonic strength has him pinned down quite easily. "Now don't worry dear, this won't hurt a bit", you say while baring your fangs. You move your mouth over to his neck and sink them down in one quick bite, making the man scream in terror and pain. In seconds, his skin starts to change to a deep red color, and claws growing at the ends of his fingers and toes. You open his mouth and see his fangs and tongue have already formed in the meantime. Small protrusions start forming on his forehead, quickly growing into short, milk-white horns. His spine seems to have changed a bit as well, allowing for the growth of a long pointed tail, starting as a small point above his butt and rapidly roping out into a lashing demon tail.
"Now comes the fun part", you say, "I'm not just gonna let any man into my legions..." His chest flesh suddenly starts to inflate, pumping up the red skin into nice round D cups and with a slight pop, the appropriate nipples form on top. Finally, his red penis and scrotum quickly become shorter, vanishing into nothing to be replaced by a pair of thick red vagina lips. "aaaAAH!", she screams in a shifting soprano voice as the pain becomes too much to bear. You grin..."Welcome, my new succubus. You are now my eternal slave."
"How may I serve you, my mistress?"