She surprises him...

He expected her to shudder in fear. To scream, to protest, if only for a moment. There was none of that. Instead, her mouth opened not in terror, but in excitement. He felt her arms and legs, wrapping around him, her soft chubby body leaning against his, filled with affection.

"Do it." her voice was both sultry and soft, high-pitched from desire and filled with both lust and other, gentler feelings. "Who cares about my soul? Take me now!"

He was confused, for a moment. The sadistic side of him felt annoyed that his victim did not resist. The remnants of his humanity felt relieved that he did not have to **** himself on one of his closest friends. Most of all, he was shocked by such a reaction. It was as if she dreamed about this. Fantasised about this. But about what? Being taken by a demon, or by him? Or both?

Then his demonic nature took over, and all his thoughts stopped. Instinctively, he grabbed Mab, and pushed her into a forceful kiss, while tearing her top. He could hear her whimpering under his touch as his clawed hands ran through her soft skin under the fabric - he was not quite sure if it was pain, pleasure, or both, but he was excited by either. He was even more ecstatic when his human girl started answering the kiss.

Now completely under Timothy's sway, the plump girl looked into his eyes with a blissful gaze. She arched her body, letting him rip off the remains of her clothing, and then moaned in ecstasy when her top fell to the ground and the demon felt her massive soft breasts. Overwhelmed by dark pleasure, she started grinding her exposed pussy against Timothy's legs, eager for the wild sex to come. Soon, she felt something hard brushing against her thigh. Good.

Inbetween the long, passionate kisses and sensual caresses, Mab moaned some sweet-nothings to Timothy - something about how she always loved him and how she wanted to be his and his alone. The incubus, if anything, was amused. The affection was touching, but her dreams of monogamy were almost painfully human. Fortunately, she'd soon be fixed.

"M-master--" moaned Mab. "Please, I can't wait anymore--"

"Can you?-" Timothy smirked. Suddenly, he pushed his lover forcefully on the bed, forcing a panicked, yet excited yelp for her. As he came closer to her, he took a good look at his Mab's nude form. Even as a human, there was a certain unique charm to her. Her large dark eyes, filled with intense affection, her long curly hair, and her unearthly curves made the demon-boy more aroused than ever.

"Y-yes, yes, please, anything, just fuck me..." the lust-addled Mab moaned. She now lay on the bed, legs spread, her fingers rubbing her moist pussy almost unconsciously. She watched excitedly as the handsome demon slowly approached her, and almost screamed in ecstasy as he grabbed her by the thighs.

Her eyes still fixated on her Satanic lover's face, she didn't see his monstrous dick entering her - but when it did, she felt it immediately. An outburst of pleasure radiated from her pussy to her body, and her mouth open in wordless bliss. Then it thrust inside her again, then again, and again--

"Ahhh--"

The incubus made sure to fuck Mab hard, but slowly, intending to prolong the pleasure of corrupting his former friend. He grinned sadistically as he watched her lose her mind from the ecstasy more and more with each passing thrust - first whimpering quiet proclamations of love, then depraved obscenities, and then barely coherent demands for more.

"Ahh-- please-- fuck me harder--"

Tim increased the pace of fucking, adding his demonic tail to fuck her ass while he groped at her fat tits.

"Moan for me, whore."

Mab couldn't say no. Not when the demon cock penetrated , faster and harder each time. She did as she was told and moaned - first in her normal high-pitched voice, then more and more deeper and whorishly, as her morals and inhibitions crumbled. Tim looked with perverse glee at how he turned Mab into a slut - even if he knew that was only the beginning. He continued fucking her harder and harder, her moans louder and louder, until the two felt their orgasms approach.

"Ah-- you told me... I have to give up my soul?~" Mab said inbetween the moans and thrusts. "You don't have to trick me into it--" The demon grinned. "I give it willingly-- just please-- let me be yours--"

"Good-- little-- slut-- AAH--"

Tim couldn't finish his words as he finally came, his black demonic seed filling his lover below him as her soul finally came loose. As he savoured the essence of the purity and innocence Mab abandoned, he watched her eyes start to glow fiery orange, as her body's transformation began.

The transforming girl embraced her devilished lover with her arms and legs, as bursts of pleasure coursed through her changing body, opening her mouth to reveal her sharpening fangs and long, forked tongue. Her small, chubby form was changing into that of a demonic seductress, to match her now-depraved mind - a combination of Tim's idea of a perfect woman, and her own fantasies of what she could become. Her once-wide waist narrowed (though retaining certain plumpness), while her breasts and ass grew to become even larger which, together with her short height, gave her a delightfully curvaceous figure. Mab's once tame brown hair burst like a waterfall from her ponytail, becoming a wild midnight mane with purple streaks. They seemed to match her skin tone, which changed from her Middle Eastern olive into an unnatural demonic violet.

"Ahhh-- yes... fuck being a human..."

Tim looked with delight as his Mab turned from a weak human into a sex demon just like him. He noticed as her moans of pleasure became more and more whorish, her voice lowering and gaining this seductive overtone. He saw the look in her eyes - first full of fear, then of pleasure and then, finally, sexual hunger. Everything that was pure and noble inside her vanished, replaced with the hellish, never-ending lust of a succubus. This was the Mab he wanted.

"Satan be praised..." Mab whispered she cupped her now-huge breasts, playing with her own nipples. "...Yes, this feels so... fucking... GOOD--" Suddenly, she gasped as another burst of pleasure hit her - a crown of long, curved horns burst out of her head, while a long, cock-tipped tail emerged from her now-gigantic ass, curling around her thighs. She looked at it excitedly and moved it towards her lover, entwining his leg to bring him closer to her.

Their energy now spent, the two demons collapsed on the bed, facing each other. Filled with utter bliss, Mab still couldn't put her eyes away from her Timothy. She gently caressed his face with her now-clawed hand as she reached closer to him to pull him into a kiss. Her eyes, now burning orange and with serpentine slits, were now filled only with lust, cruelty, and pure desire for her new master.

"Ohhh-- Satan be praised-- I dreamed of this for so long..." she whispered, half-seductive, half-lovestruck, as she nuzzled in her lover's embrace. "Just... you and me... together, in this bed... mmmh--"

"What, horns and all?" Tim quipped. Mab giggled a little, and then nodded.

"Oh, sometimes. I had a lot of fantasies..." Mab smiled. "Sometimes you were a gangster **** me, sometimes you were my stepbrother secretly wanting to fuck me-" - the two demons grinned, recognising their new incestuous urges - "And sometimes, you were a demon. I had a thing for monsters, you see."

"And now you are one yourself."

"And I LOVE it." Mab ran her hand over Tim's torso and licked his face with her long forked tongue. "I always wanted to be a bad girl-- and who can be more bad than a fucking demon from Hell?"

The violet-skinned succubus spoke in a sultry, sensual tone, clearly revelling in abandoning her shy nerdy self to become the filthy whore she was now. Tim couldn't help but harden just from the sound of her voice.

"Now--" Mab continued with a lecherous smile. "I'm bored of talking." Tim felt his lover's hand grabbing his dick, "Time for round two~"

It took a few dozen rounds and a few hours to finally satisfy the newly transformed demon couple. The two hellspawn experimented with fucking in all sorts of ways - dominating and being dominated, slow and passionate as well as rough and fast, Tim filling his lover's every orifice, and occasionally being fucked in his as well. It wasn't until sunrise that the demons finally could think of something else than sex.

Looking into the morning sky, the redhead incubus and his violet-skinned succubus lover contemplated their plans for the day. There were so many victims to seduce, and so many ways to fuck them, yet they could only pick one at a time...