Emily eagerly impaled herself on Brian, his hard cock easily sliding into her. Brian couldn't believe what was happening: he was losing his virginity to his next door neighbor that he had a crush on who had broke into his room because she transformed into a succubus. Part of his mind told him he had to be hallucinating or dreaming, but it seemed incredibly real and he hadn't taken any drugs. He tried not to think about that as Emily rode him, doing far more of the work that his thrusts. His hands reached up to take her breasts, which seemed impossibly perfect.
Brian didn't know it, but the succubus mounting him had been a virgin when she woke up that morning too. That fact hadn't even crossed Emily's mind and the way she was fucking nobody would have mistaken her for one. Such was the power of being transformed into a succubus. She slid up and down on Brian like an expert, her perfect pussy playing working beyond his wildest dreams. Emily managed the pace well enough to keep Brian going several minutes longer than he should have been able to, but with one final thrust she drove Brian as deep into her as he could go and put both one hand over Brian's mouth and the other over her own mouth to stifle any scream. The succubus felt the warm liquid of life filling her and her muscle pumped Brian until his dick gave its finally spasm and squirt.
Emily dismounted from Brian's limp body and sat on the bed next to him, her back against the way. She felt so amazingly fulfilled. The horns began to shrink back into her forehead and her tail back into her tailbone. However, her breasts seemed to remain in their changed condition, not that she minded. As her body returned (mostly) to normal the haze lifted from Emily's mind. Without the desperate, overriding need for sex she could realize what had happened. She remembered everything and realized she'd enjoyed it. Looking over Brian's naked body, she didn't feel any regret. They'd both enjoyed what happened. Brian was silent, exhausted, drifting back into sleep. She leaned over, kissed him on the lips, and whispered "I'll see you again." Then borrowing some clothes, she left via the same way she got in.