Samantha sensed sexual energy coming from the adjacent bedroom belong to her stepbrother, Mark. Mark's father and Samantha's mother had remarried a decade ago. The step-siblings had gone through awkward teenager years together. Not just because he was a cool kid and she hung out with goths and wiccans. Samantha had caught Mark leering at her a few times she hit puberty when he thought nobody would notice. Now he was a fratboy college senior.
Mark was sitting in a chair with his phone in one hand and his other hand down his boxers when he felt a sudden rush of warm air and a faint hint of sulfur. He turned to see Samantha standing in his room, looking at him in a way she never had before.
"S-S-Samantha?" Mark stammered. "What are you doing in here? Wasn't my door locked?"
"It's still locked" Samantha replied. "I didn't use the door."
Mark was confused. He didn't notice Samantha's horns. Her wings were folded behind her out of view, and her tail likewise behind her. He just saw his stepsister in a very tight corset and very short skirt. He hadn't thought about her while masturbating since he went to college and started hooking up with sorority girls, but if he had wanted to imagine her sexy he couldn't have done much better.
Samantha walked over to Mark and leaned over, giving him an excellent view of her ample cleavage. Her hands grabbed his thighs. "You're horny. You've lusted after me for years. Look me in the eyes and admit it."
Something in Samantha's voice compelled Mark to look away up from her chest at her face. Her face was flawless. Her lips full and dark with black lipstick. Her eyes framed by the darkest eyeshadow. But in her eyes he could see the burning desired.
"I want to fuck you. I've wanted to fuck you for years." Mark had never admitted it until now.
Samantha went down on her knees in front of Mark and pulled his boxers off, revealing his erect cock. She took it in her mouth, using her new demonic tongue to show Mark pleasures no sorority slut could show him."
Mark couldn't believe what Samantha was doing, or how well. Her tongue was inhuman. Then he noticed the two horns on her head, now to close to him to miss. Her leathery wings unfolded and her tail swayed. His stepsister was a succubus! He suddenly realized of all the stupid hookups he'd had in his life this might be the dumbest, but he wasn't going to stop and he didn't think he could if he wanted. As Samantha pleasured him, he impulsively grabbed her horns and held on as her tongue continued to do it's magic. Mark realized she wasn't coming up for air either. Samantha was deepthroating him. He didn't know how he lasted as long as he did before he finally climaxed, pumping and pumping until finally slumping in the chair.
Samantha stood and licked her lips. Appetizers were delicious but she still desired the main course. She effortlessly hauled Mark from his chair and tossed him on his bed. He was momentarily spent, but like any good succubus she had ways of revitalizing his stamina.