Reluctantly

Sara looks at you. "Fucking attenuated virus, has really messed with your mind. You know I don't think I can catch it again?"

"The virus isn't so bad Sara. It frees you, makes you the slut you were always meant to be." You slip a finger in your sex for emphasis. She turns away. "And, if I can't infect you at least I get an orgasm. So...are you going to eat me out?"

"Allright Greta, it's not like I have a choice, deal."

The hounds drop her and she crawls to you. You drop your skirt and she begins to lick. You are impressed, she has picked up some new tricks. Soon you are wet and moaning. You slip a taloned nail beneath your Greta suit, and cut yourself just above your sex. Soon your black blood is mixing with your juices. You grab Sara's head and hold her tightly to your sex. She swallows copious amounts of your blood and juices as you come.

"Oh! Fuck yah!"

You drop Sara. She licks her lips and has a puzzled expression. "So, are we free to go?"

"Of course. Let me help you up."

You watch the darkness within her stretch and grow. As you pull her up she grasps her stomache.

"Are you feeling Ok?" You ask with mock concern.

"Yah, just a little weird, that's all."

You lean into her, while calling demonic magic. "Why don't you go fuck Jack. Then send his soul to hell." You watch as the dark tendrils of your magic slip into her ear and take root. Your power to fuck with the human mind is not unlimited. You can only nudge them to do what they already are willing to do. Fortunately Sara hasn't slept with Jack and her desire for him is palpable. You can only hope her growing demonic nature will really want to destroy Jack's soul mid rut.

She makes her way over to Jack. "Jack we're free to go. First I really have to do this."

She gives him a passionate kiss. Between her own growing powers and the demonic taint you have filled the room with, he is immediately erect. She slides off his pants.

You hear her whisper in his ear, "Fuck me, Jack."

"Shh...shou...shouldn't."

"Why not baby, no darkness is stronger than love."

She slides into the injured man's penis and begins to ride him. You watch as her eyes go from drab human orbs to exciting red slits and back. Toward the end they settle in as demonic slits. You finger yourself to orgasm as you watch Jack come.

With her own soul clinging to her by the barest of threads, she rips his out and sends it to the pit. You watch as the vileness of the act utterly destroys her soul. Her transformation quickens. You thought your transformation was fast, but hers is lightning by comparison. Streaks of red appear by her pussy. Inside of a second her whole body is the gorgeous flawless red of a demon. She screams as horns, wings, and a tail all burst through simultaneously. She stands and in a blink she goes from attractive to the over ripe beauty of a creature from hell.

You name her. "Succubus! How do you feel?"

"Wonderful, mother." She revels in the wrongness of calling you that. "We were genuinely in love, do you know how hot it was destroying his soul? I'm getting wet just thinking about it."

You admire her. She is vile, twisted, and ambitions,. You couldn't have hoped for more. For enough power she would gladly kill you, but for now she will serve.