Transforming His Sister

This is a short work of erotic fiction containing furry, or anthropomorphic, characters, which are animals that either demonstrate human intelligence or walk on two legs, for the purposes of these tales. It is a thriving and growing fandom in which creators are prevalent in art and writing especially.

All work is fiction intended for fantasy only, regardless of content, and consent must always be acquired when engaging in any sex act with another adult.

Please note that all characters are clearly over eighteen and written as such in all stories.

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Matt took a breath, though it didn't do anything to stave off the frantic hammering of his heart. He wasn't doing anything -- yet -- that should have been stressful, but it was hard to think of it as anything other as he paused outside the door of his sister's room. His blonde hair had been trimmed recently and no longer tickled around his ears as much as before, but he almost missed the sensory distraction. It may have made the breaths come more easily in his chest, yet it was merely excitement tangling with anticipation that clawed at him.

Matt... Well, he'd got his hands on something supposedly very interesting, even if he'd not had the chance to try it out yet. A seedy online source permitted him to download a "magical transformation app" to his phone; even the name seemed rather stark, promising things that surely could not be true. But he had to try, even if he'd wasted his money on nothing, eyeing up the door, which held so much promise behind it.

"Okay, here goes nothing..."

He said the words out loud to himself, as if they would give him strength to go on, but it was really only jumping into the moment that was going to get Matt in motion. He opened the door to his sister's room without knocking -- and took the plunge.

"H-hey, Cynthia."

He stumbled over his words, pushing them from his tongue as he tried to appear normal. His blonde-haired sister was sitting on her bed with her ankles loosely crossed, wearing only an oversized T-shirt and panties. That in itself was not unusual, as they were pretty comfortable wearing little clothing around each other in the house, but his heart still leapt. Yet he could not help but take in her in, her thicker, softer thighs and the shirt that tempted at a glance of her hip. Just being dressed casually, Cynthia didn't seem to have bothered with a bra in the house either.

"Hey, Matt, you okay?" She said breezily, a smile dancing across her lips. "Knock, much? Well, it is you."

"Uh, yeah," he said, running his fingers back through his hair, stalling for time. "Yeah... I should have knocked, I'll do that next time."

But, if the app worked, that was soon to become a moot point. He held up his phone, pretending he was just fiddling with it, while Cynthia's eyes slid back to the TV show she was watching. Bringing up the app on his phone, he pointed it at her, bringing her into view on the AU system. It was simple to start, allowing him to input commands once the person had been identified, but any muddied or confusing commands would not go through. So, that meant he would have to be specific about what he told her to do, or to change.

But the app surely would not really change her...would it? Even then, he could not be sure.

"Matt, what's up?"

He said nothing as he tapped the three hearts on the app, increasing love and affection. Surely, that would be a good place to start. Adding one extra command, through the text input screen, he wrote: love me and flirt with me.

He could have been even more specific than that, of course, but he wanted Cynthia's personality to shine through -- if the app even was to work. It wasn't that he wanted to change who she was, just more about how she felt towards him, for that underlying attraction, what had him lying in bed wakefully night after night with his need throbbing... Well, Matt had not found it easy at all to set aside just like that. It had been pervasive, digging into every last little corner of his life and world, and he simply had not been able to resist his burning attraction to his sister.

Whether it was right or wrong was not something Matt was going to consider. In a scenario like that, it simply lost all importance.

Yet, to his surprise, as the app recorded his commands, his sister's expression softened and warmed. Cynthia looked at him in a way she never had done before and sat up a little straighter, bringing her legs under her in a scuffling reorganising of limbs that rumpled up the bedsheets somewhat too. She cocked her head at him, her cheeks lightly pink, and pushed her shoulder blades back. In a way, it was as if she was subtly trying to draw his eyes down to her chest, her shirt draping sensually over her breasts. Even her nipples showed lightly through her shirt, the small peaks questing curiously against the soft fabric.

"Mattie..." She murmured. "Why won't you come over here and sit on me? Are you really going to make me ask for it?"

"Hm?"

He started but was curious enough to cross the distance between them, his mouth dry. Matt sat gingerly on the edge of the bed, although Cynthia wasn't having any of that. With a giggle, she flung her arms around him and dragged him back on to the bed, toppling to the mattress and sheets with a muffled thump.

"Oof -- Cynthia!"

He wasn't trying to stop her in any way, just coming to terms with the shift between them, whatever it turned out to be. She was still her and her actions could well have been innocent, even if Matt didn't at all think they were.

Maybe there really is something to this app?

Matt could only hope, after all, as his sister knelt behind his head, gently combing her fingers through his hair. He hummed quietly, barely a murmur, eyelids fluttering. Oh, that was so relaxing... Almost better than lust, more like...actual love. Caring. Kindness. Those words and more flitted through his head, easing his experience with reality as he let out a long, relieving sigh.

"Thanks, Cynthia," he said gently, checking the phone and trying to decide what more he would test on her. "I love when you do that... You look great in that shirt too."

"Aw, Matt, you're so sweet!" She cooed with a blush. "Thank you, I wore it just for you."

He wasn't sure what that meant, but it was hard to keep his eyes away from her panties as she knelt so close to him with her knees apart so her hips were a little lower on the bed than they should have been. His breath hitched on his chest and he input another command without thinking twice about it: make Cynthia accept anything I ask or tell her to do.

That seemed a lot...but Matt didn't want to abuse it, no, not really. At least, that was what he told himself as he confirmed the command and tipped his head back to watch his sister's reaction. She rolled her hips a little closer to him, the front of her abdomen brushing lightly against the back of his head, making his heart skip a funny, little juddering beat all over again. In his shorts, his need thickened slightly, but Matt didn't think it was so much of a problem anymore.

Many things that would have been problems... Well, those issues no longer existed.

"Hey, sis," he said lightly, as if the thought had only just occurred to him. "Can you let me look at your feet? They're so pretty when you put polish on your toenails."

"Aw, yeah, of course," she said, scooting back as he rolled over on to his front. "Come here, Matt, you can do anything you like with my feet!"

She brought her feet close together, sitting back on her buttocks as she bent her knees, putting him in the perfect position to admire her lightly wriggling toes. Cynthia giggled, heat seeming to creep further down her neck from her rosy cheeks, yet he didn't think it was at all an embarrassed blush. It was something deeper than that, something that had her squirming in turn, biting her lip as she tried to look at him without looking directly at him.

"Mmm, thank you, Cynthia..."

He breathed the words like a prayer as he ran his gaze appreciatively over her feet. Cynthia raised the left one and flexed it softly for him, scrunching up her toes and then stretching out her whole foot again. The pull of skin across her sole was simply hypnotic and he let out a soft moan as his very own beautiful sister fulfilled his fantasies without even truly knowing what she was doing.

He grabbed a foot and pulled it towards him, propped up on his elbows for a little more room. Kissing her toes, his heart surged and he found himself unable to help his base desires, wanting to do no less than to fulfil his fantasies, all the things that had been going through his head, day and night, since his attraction to Cynthia had grown. The soft skin of her toes, her feet beautifully kept and softened with creams and soaks, brushed his lips as he kissed them, almost offering her a faintly ticklish sensation.

"Hee -- Matt!"

He smiled at her and they exchanged a look, enjoying the moment. Yet it was a shared moment between the two of them, even if the app had changed Cynthia's feelings towards him. Or maybe he could think that love had always been there and he was just the one letting it out into the light to really shine, removing that one, last barrier between them. But that would only be his own mind as he salaciously and lewdly enjoyed himself.

He moaned as he lapped gently over her toes, his tongue sliding between the big one and the one next to it as he pulled her toe into his mouth. His heart surged and Matt sank deeper still into the moment, enjoying every second as he slurped wetly on her foot. Her toe felt thicker in his mouth than it appeared and he swirled his tongue around it, marvelling at the fact that Cynthia was just allowing him to do it all to her.

Matt almost completely forgot about the app on his phone as he worshipped her feet, lewdly swapping to her other foot as he sucked on her toes, his tongue sliding straight under them. He couldn't help but take the time to caress and lap gently over the fleshy underside, feeling how each and every one of her toes was different, offering him a slightly different sensation every time. Oh, how he wanted to map the contours of those toes, to memorise each nuance and curve.

Yet all he could do was stay there in the moment, adoring her body as she accepted everything he did to her. He folded his lips succulently around her big toe on her right foot, drawing it deep into his mouth as if it was a sweet treat he wanted to devour. When Matt withdrew, her toe was shiny with his saliva, although that would quickly dry.

"Aw... Are you enjoying my feet, Mattie?"

She cooed at him, her voice soft and her eyes kind. Matt twitched. He'd almost forgotten what he was doing, that he was there with his sister, doing the kind of things that, of course, were not typically allowed between brother and sister. And yet his heart still warmed with lust and love for her, brimming over. It had to come out one way or the other and he kissed over the top of her feet, making sure he caught and adored each and every one of them, not wanting to miss a single tremor of the moment.

"Thank you... Thank you, Cynthia."

He shook his head a little, lips tugging up in a smile. Pulling back, he took both of her feet in his hands and pressed them together, admiring how the light glanced off the top, the shadows that fell around the insides, like a secret lay between them he only had to plunder to uncover. Even adoring her feet with his eyes was something he hadn't been able to enjoy fully before, sneaking glances here and there. Yet Cynthia flexed and curled her toes lightly for him in that moment, allowing him to enjoy both view and feel -- and, of course, taste too.

"Cynthia..." He murmured, casting his gaze shyly downward as he kissed her feet again, his lips parting lightly over each big toe. "You're so amazing, thank you for letting me be with you this way."

"It's the least I can do, Matt," she said, eyes shining with earnestness. "I'm glad we get this time together..."

She looked like she was going to say something more than that, but Matt wanted to control their time a little more. Maybe that meant Cynthia couldn't quite shine as he wanted her to, but there would be plenty more time for that if the app itself worked. And, so far, it seemed to work well as his sister leaned in and kissed his forehead, folding forward over her legs, which were still gently bent in front of her.

"Hang on, sis."

He paused her as he grabbed his phone. He didn't have to think to input another command into the app, though he paused again. There was one thing he needed to test.

In the app, he typed, "Make Cynthia take off her top."

As she wasn't wearing anything else on her top half, other than the top, Cynthia did so instantly, responding to the app. She drew her top up instantly over her head and stretched out her arms, her breasts rising as she took a deep breath. Yet Matt caught the cheeky look she sent his way too, his sister teasing him naturally too.

His eyes locked on to her tits with greedy intent, but who would not have been able to stare at breasts that were so full and large? They pulled down very lightly under their own weight, but that was merely a factor of their size. The heaviness of them begged the touch of his hand and he ached to press his fingers into her soft flesh, pale where she had not tanned her breasts. The tan on the rest of her body was so subtle, however, he had not even noticed it when she'd had clothes on, though the tan lines on her shoulders and breasts were obvious once she was topless.

Matt took a breath. There was just one more thing to test as he set his phone down, offering his sister a genuine smile.

"Cynthia... Please, take off your underwear too. I want to see you, just as you are."

Cynthia did so without question, even though there was a little giggle bouncing from her lips. A hint of a blush deepened the colour on her cheeks and she shifted her weight as she kicked her legs out over the edge of the bed, sliding her underwear down seamlessly. She flicked it off the end of her toes with a light-hearted laugh, turning back to him as she cast Matt a look over her shoulder. That look, however, was anything but coy as Matt's heart skipped a beat.

She was hot. Of course, Matt already had known and thought that for himself, but it was different seeing her nude before him, bare and in the flesh. Cynthia had breasts that were a good size, undoubtedly, but it was how they suited her body so very perfectly that made him want to hold them in his hands, to sweep his thumbs over her areola and see her arch deliciously into his touch. Her nipples perked up and, although there was more of her to adore, he didn't resist sliding off the bed and sinking down before her, so he could take one of her nipples into his mouth.

"Mmmm... Ohhhh!"

Cynthia moaned beautifully and arched into his touch as her body quivered, a rolling desire coursing through her. She might not have quite known what was driving her on to be with her brother in that way, but she didn't care either. She followed the draw to him as she moaned and let him suck on her breast, Matt's fingers curling devoutly into her other tit as he squeezed her flesh reverently.

"Mmmm... Matt..."

Oh, he loved how her name sounded on her lips. It was much better than him sounding out his own name from his mouth. Cynthia was different, she was special. She was someone that made him a better person.

The fact that he was using the app to control her, however, might have rendered that a moot point, but they were still in alignment, in some way. He didn't honestly believe his sifter felt nothing for him as he kissed and nipped passionately at her nipple, raking his teeth lightly over it just to see how his sister would react. Cynthia's moans were more than enough to usher him on, groaning in the back of his throat as he sucked her nipple fully into his mouth.

There, he played his tongue around her nipple, flicking it up against the underside. The moment was his as he enjoyed it, her nipples hard in the cool air of the bedroom, though he didn't want to leave the other out as he swapped to her other breast. The cool lick of his saliva layered her nipple and Cynthia moaned her brother's name all over again, rolling her body sensually into his touch.

One thing he had to change, however -- and that wasn't one he wanted to wait around for, if the app could make quick physical changes too. He broke from her breast and laid his head against Cynthia's shoulder for a moment as he made a quick update in the app to make her currently clean-shaven pussy hairy.

Lots of hair. He wanted it all and pulled back to watch as it bloomed on her body, transforming lustfully as he panted softly, his lips parted.

"Yessss..."

Matt let out a long, rolling hiss as he watched the hair grow on her crotch. It was a mid-tone blonde, though dark enough to stand out just a little more on her pussy, which Matt was quite glad of. He was sure, using the app, he would be able to change the colour of it too, if he wanted to.

But he was more than glad to stay in the moment as he moved up on to the bed, sitting on the edge while looking down at his sister. He'd never felt a hunger like that in him before, how it growled and clawed at his insides, demanding something of him he could, at the very least, fulfil.

"You're amazing, Cynthia," he all but growled, even though such a tone to his voice was not something that came naturally to Matt. "So hot... Please... Give me a blowjob. I want to feel your lips on me so badly."

She helped him out of his clothes, his sister moving with her own intent as she got him down to nothing at all, though it didn't take long. His rising hard-on sprang to attention as he groaned and let her hand close around it, her fingers folding so perfectly around his cock that it was as if they were meant to be there. Yet Cynthia appeared more than ready to take his shaft into her mouth at the same time, her lips folding smoothly around his cock as she sucked on the head.

"Ohhhh, Cynthia!"

He moaned and dug his fingers into the bedsheets so he didn't grab at her, wanting his sister to deliver pleasure to him just as she wanted to. It wasn't something for him to interfere in when his heart was pounding as desperately as it was, almost longing to push him on into something more while he was there to languish sweetly in the moment. He didn't want to rush when it was all something he had wanted to experience for so long already.

Her head bobbed on his cock, lips perfectly pursed around his length. Matt's heart leapt and he gasped for breath, watching her lips descend and rise, over and over again. He grabbed at his phone while she was giving him a blowjob, her hand gently roaming over his thigh and under his nuts, exploring him too. Even that was enough to somewhat distract Matt as he juddered, rocking his hips lightly so his member speared a little deeper into his mouth.

Regardless, he wanted to let his sister do as she willed, her tongue luxuriously cradling the underside of his cock as she moaned around him. She arched her back, pushing her ass out a little more, and Matt's eyes hungrily ate up her form, even though he wanted to run his hands all over her, his cock throbbing wantonly within her mouth. He groaned.

"Ah, fuck... Yes, Cynthia..."

She mumbled and moaned his name around his cock, though Cynthia was in her element, thinking of nothing more than her partner of the moment. Her lips slid smoothly along the length of her cock as she slurped along him, leaving a gleam of saliva on his shaft.

His focus was on the app, however, changing things further as he added more hair to her body -- a lot more hair. Changing the colour too, for his inclination swung that way, he groaned in the back of his throat: a deep, rolling sound that ached from the core of his being.