“Why am I doing this…?” Fluttershy sighed as she looked herself in the mirror, naked and blushing furiously. She had no clothes laid out to wear, nothing other than the cute, frilly pink apron that Zephyr had bought her recently. She was reluctant to put it on, not so much because she felt embarrassed at the prospect of her brother seeing her in literally nothing other than an apron--he’d made he wear it in front of him before, after all. And it most certainly wasn’t because she was starting to kind of like the attention that he was giving her… It was the knowledge of what she knew was going to happen once Zephyr got back from his work at the Ponyville Day Spa.

Namely, the fact I’m going to have... sex... with my brother. Under completely normal circumstances, this would sound perfectly absurd. Not because it was taboo--Equestrian law was very vague when it came to the topic of incest between two consenting adults--but because she was the one who promised him, her bonehead of a brother, that if he did a good enough job and got a promotion at the Spa, she’d let him have sex with her.

She found herself covering her face in embarrassment. “How’d I let it get like this...?!”

Of course, she knew the answer to that herself.

It had all started shortly after Zephyr had finally left their parents’ house to strike out on his own. Having gone back to and graduated from his mane therapy course, he’d had moved to Manehattan to work in the big city. For a while, things were actually going rather well for him. He’d landed a pretty good job doing what he was passionate about, had found and moved into a good apartment to live in, and was even sending bits back to their parents to make up for when he’d been taking advantage of their hospitality, genuinely sorry for how he’d behaved before.

Aaaand then his apartment caught on fire. And that fire destroyed pretty much all of his belongings. And with no place to stay, he’d had to quit his job in the city.

She’d told him those scented candles were a bad idea.

But in all seriousness, it was a genuine disaster for Zephyr, especially considering he’d just turned over a new leaf. To his credit, he’d refused to move back to Cloudsdale just so he could go mooching off their parents again, but she knew that this was exactly what her brother had been afraid would happen--failure.

Ultimately, she decided to let him move in with her, at least long enough that he could get his bearings back in order--though she had made it clear she expected him to find work in town. Luckily, she knew he’d be a perfect fit at the spa, and they were more than willing to take him on after she vouched for him. Her being a close friend of a princess, not to mention a celebrated figure herself, might have had something to do with it.

But while all this was going on, there were... more personal developments between her and Zephyr since he’d moved in with her.

It wasn’t terribly obvious at first. Zephyr was genuinely grateful for letting him stay with her, and after he’d let go of his fear of failure and stopped being the slacker he was before, their relationship had become a lot more affectionate and mutually caring than it had previously been. They hugged and laughed and talked more, and spent a lot of quality time together. Sure, he was a bit sloppy and was an idiot sometimes, but she could say with confidence that her brother had become a much nicer person than he had been before.

But it soon became clear that there was a lot more going on with how Zephyr actually felt about her.

In hindsight, she should have seen it pretty early on. How he’d give her free, dedicated mane therapy sessions without any complaint, or massaging her even when she wasn’t tired or worn out, spending his free time making sculptures exclusively of her…

But it wasn’t until about two months into him moving in that she actually found out what was going on.

It had been late at night, when she’d been going for her usual glass of water before heading to sleep. Zephyr’s room was between her bedroom and the kitchen, and when she’d passed by his door, it was ever-so-slightly ajar, and she could hear slick, wet noises coming from her brother’s room, as well as his own grunting.

For a moment, she thought he was working late on another sculpture of his, which was, again, what he usually threw himself into as a hobby. She was about to open his door to remind him to not stay up too late, since she wanted him well-rested for his new job… only to catch a glimpse of what was actually going on in there.

He was masturbating. More than that, he was masturbating to her. He’d made that abundantly clear when he all but shouted her name through gritted teeth when he ejaculated. To say she was thrown for a loop by this revelation would have been the understatement of a century. He’d always seemed so into Rainbow Dash before, but then again, he had changed. Perhaps her stepping up to make him change his life for the better had shifted his interests? She honestly couldn’t say for sure.

And while she could have been disgusted by the fact that she was the object of her brother’s object of desires, she wasn’t considered the Element of Kindness for nothing. She might have been naive, and was certainly embarrassed at the idea of being desired after by her brother, but she wasn’t going to be a prude about it and kick him out.

In fact, she made the rather unorthodox choice to use the knowledge her brother wanted her to her advantage. She didn’t want his run of bad luck to discourage him into falling back on his old habits, and now she had a way to ‘reward’ him for keeping on the straight and narrow--if he did good at his job, contributed around the house, and generally acted like a functional adult, she’d give him sexual favors.

It had been relatively tame at first, like letting him watch her bathe and undress, or even posing nude for him when he was sculpting, but the real problem with Fluttershy’s plan was quick to flare up. Put simply, it had worked too well; Zephyr was extremely into the idea of her rewarding him for his good behavior. Soon enough, he was doing so well at his job and bringing home so many bits, that she had to escalate the favors. When he got his first raise, she started kissing him. When he got his first promotion, she started giving him head.

And before she knew it, she was his marefriend in all but name. Instead of merely watching, he now got to join her whenever she bathed or took a shower, and got to undress her whenever she was changing. Their formerly platonic hugs and kisses had become far more unchaste and erotic, with him making out with her every time he left for and got back from work. He’d also gotten her to wear nothing but her underwear whenever they had the house to themselves, so he could look at her scantily-clad body whenever he wanted. As if that weren’t bad enough, he got to freely grope and touch her at his leisure, and recently, he’d even earned the right to cuddle with her in bed.

But it had been his most recent triumph that had taken the cake. Apparently having become so famous a mane therapist as to warrant the attention of the royal sisters themselves, Princess Celestia and Princess Luna had scheduled an appointment with him, at Twilight’s own recommendation to boot. The two sisters were quoted to have said ‘their manes had never felt so ethereal, or waved more majestically in the wind--nonexistent or otherwise’.

It was probably the crowning achievement of her brother’s life. Their parents had been so proud of him when they’d heard the news--and Fluttershy would be lying to herself if she said she wasn’t gleaming at her brother’s following fame.

It was just… well… after something like that, she figured she had to give him something very special to show how proud she was of him… and only one thing really came to mind.

She had told herself when it had all started that it wouldn’t come to sex. She thought that she’d never find herself actually giving herself to her brother when she first decided to give him sexual favors.

But the more that Fluttershy had thought about it… the more she realized that she already had given herself to him. Short of actually letting Zephyr inside her, he could already do almost anything he wanted to her, and she couldn’t really complain. After all, she’d been the one to let it all happen.

Not to mention, as hard as it was for her to admit, he had actually gotten really good at pleasing her. He could have been a unicorn in another life, because sweet Celestia, he had hands that would work magic on her body. And the way he could eat her out, the way his tongue lapped at her mound and parted her depths…

It left her feeling both pointedly aware of how long it had been since she’d actually had sex, and simultaneously frustrated at how easily she was letting him wrap her around his finger. She certainly never told Zephyr how much she was finding him infuriatingly satisfying… Still, after hearing about how he’d made a name for himself by earning the glowing recommendations of the royal sisters, she told him that they were going to finally go all the way.

And so, here she was, in the bathroom, waiting for her little brother to get home... so they could make love.

“I don’t have any right to complain,” Fluttershy told herself, sighing. “I started this, so now I’m going to see this through. Maybe… maybe after this, I won’t have to give Zephyr any more of these favors.”

That wasn’t going to happen, and she knew it. She’d let Zephyr have a taste of her, and like a thirsty camel takes to water in the desert, her horndog of a brother now couldn’t get enough of her.

But almost unconsciously, she also wondered to herself, “...Would I want him to stop?”

She wished he wasn’t so good at going down on her. She wished he wasn’t a great kisser. She wished he didn’t know a thing about making her feel good. And she really wished that he didn’t have that big dick of his that she could only barely take down her throat… That throbbing cock that was going to go inside her…

She chewed on her lower lip, and scrunched her eyes shut as she desperately tried to ignore the deep pink-red blush on her face--or how furiously her thighs rubbed together, making her dance in place. She whimpered, before regaining enough composure to finally leave the room to do housework.

It wasn’t long before she heard the entrance of her cottage open. She was washing dishes when she heard Zephyr’s voice from the front door. He sounded more than a little excited. “Flutter Butter, I’m home!”

Fluttershy swallowed hard. Trying to keep as composed as possible, she called back to him, “I’m in the kitchen, Zephyr!” She was standing in front of the sink, with her back turned towards where the kitchen’s doorsill led to the main hallway of her home. She knew that it’d be the first thing her brother would see once he rounded the corner, and the thought made her feverishly blush at how she knew he’d hungrily grin at the sight of her.

She heard the sound of his mane therapy duffle bag thumping against the floor, and his footsteps started getting closer down the hall through her rustic abode, until she was certain he was right where she knew he’d have gotten his first look at her.

Wearing nothing at all except the frilly pink apron, she gave him a very generous view of the back of her curvy, stark naked body. Slender, lithe shoulders, an itty bitty waist, wide hips, pleasantly plump thighs which slendered at the knee into dainty little shins and feet, not to mention her sweet, bubble-like ass she knew he enjoyed so much…

Yet, she didn’t hear any other footsteps after he rounded the corner. No sounds to indicate that he was about to approach her.

Why is he hesitating? ...Is he getting cold feet? Her brother had been anything but subtle in his advances towards her so far, but perhaps the thought of actually doing the do with her had been a line even he hesitated to cross. Maybe she wouldn’t have to go through with this after all…

She found herself more than a little frustrated at that thought. I’ve gone through all this trouble just for you, Zephyr, don’t you dare back out now! She found her eyes shifting back behind her, but refused to turn her head even slightly. She felt so flustered by the entire scenario that she thought she’d die of embarrassment right then and there unless something happened. She whimpered in her mind. Pleaaaase, don’t leave me like this!

Suddenly, she felt a pair of hands seize either of her large, E-cup breasts, causing Fluttershy to yelp in surprise as she felt herself being pulled back into tall stallion’s hold, her back pressing into his front as he held a firm grip on her boobs. From just behind her ear, she heard an all-too-familiar voice chuckle to her, “Thanks for wearing the apron like I asked.”

She turned her gaze to peer back at her brother, puffing up her cheeks with a thoroughly annoyed, thoroughly embarrassed expression on her face as she looked at Zephyr, who held her in his lewd embrace, fondling at her breasts. “G-geez, Zephy,” she pouted softly, “Don’t sneak up on me like that! It’s bad enough you’ve got me looking like this...”

He smirked at that. “Oh, c’mon, you know you love it...” He pressed his lips into hers, kissing her deeply as he slipped one of his hands beneath her apron, feeling his bare hands against her flesh as he grasped one of her soft tits beneath the garment, whilst sliding the other down behind her back, until he groped at one of her equally supple ass cheeks. His tongue slipped passed her lips, and Fluttershy obediently parted her own mouth so that her own tongue could join with his, her respirations becoming a series of moans as he freely groped her body and deeply kissed her.

“Mmm~” Her brother hummed as he fondled at her ass and kneading it like a patty of fresh dough, before slowly gliding his hand off of it, fingers grazing ever so slightly around her thigh, disappearing beneath her apron as he began reaching between her thighs. Fluttershy gasped when his fingers rubbed against the wetness of her honeypot, though that could have just as easily also been caused by him pinching at her her nipple with his other hand, or from his deep, lewd kissing. His grin was almost insufferable when his fingers touched the sopping warmth that had been radiating between her legs, her vulva slick with desire and need. “Glad to see I’m not the only one who's eager.” He nuzzled his snout into her mane, and she shuddered sweetly as he audibly breathed in the rosy scent of her shampoo and conditioner, like a dog taking in the scent of his bitch.

I am his bitch, now… She thought to herself. She had almost no power over him in that moment, when he roamed his hands all over her and made her feel so wonderful and loved.

“You look like you’re ready to go right now, Flutter Butter. Gods, you have no idea how long I’ve dreamed about this...” He said lustfully, hungering desire plain in his voice.

“W-wait,” Fluttershy moaned out breathlessly, trying to at least get a word in with him. “Please, Zephy… not here...” She gave him a pleading look, trying to cut through the horny expression on her face.

He smirked, raising an inquisitive eyebrow at her. “Why not? Didn’t you say we could finally have sex? You aren’t backing out, are you?”

“N-no, I’m not, but,” she stammered out, glancing away from him as she blushed demurely. “It’s just… you did so well the other day, and it’s been so long since I had sex with anypony.” She looked back up to him, giving her the biggest eyes she could muster. “I… I want it in my room… so it can be special…” Also, the condoms are on my nightdesk. “Please, Zephy?”

At that, her brother’s smirk softened, and he looked genuinely touched by her request. A blush of his own fell across his face, and he scratched at his cheek bashfully. “W-well... if it means that much to you, Flutter Butter, sure! Let’s take you up to your room!” He moved himself from behind her, and slid his hands from groping between her legs and breasts.

She blinked in some confusion at his last bit of wording, and at when he placed an arm around her back. “I can walk there just fine… wait, what are you doiieeEep!” Before she had time to react, he reached down his other arm to the bend in her knees, and in hardly a second, Fluttershy was quite literally swept off her feet by her brother--finding herself being carried in his arms just like… just like…

When did he get so strong?! Oh, Celestia, he’s carrying me like I’m his bride…! She instantly covered her face, trying to hide the deep red blush on her cheeks.

“Hey, now,” Zephyr said to her in a chiding voice, and she felt her brother pull her close to his body, gently squeezing her legs and back. “You gotta hold onto me, ‘kay? Can’t have you falling down and hurting yourself.”

She didn’t even have the fight in her to protest, and so she quietly wrapped her arms around around his shoulders as he brought her from the kitchen up to her bedroom in a bridal carry.

It was as strangely endearing as it was infuriating to Fluttershy how her brother could go from being almost obnoxiously lecherous to shockingly tender at the drop of a hat. Just when she thought his pervertedness would reach unbearable heights, he’d do something so ironically sweet--dare she say, even romantic--that it just seemed to melt away any and all frustration she might have harbored towards him. It was probably why she’d become so weak against his advances, and she was more than a little annoyed at how easily he was able to sway her with the tiniest amount of romantic endeavor on his part.

Still... this is nice, she mentally admitted--she’d never let Zephyr hear that, because she knew she wouldn’t hear the end of it if she told him. Instead, she just quietly nestled into his chest, closing her eyes as she let him carry her off to her room.

She was just starting to get comfortable when he finally stopped, awkwardly but gently putting her back on her feet right in front of her bed. No sooner than she had regained her footing, Zephyr began untying the side straps from around her lower back. Once it came undone, and the apron slid from around her torso, he then hooked a finger from beneath her apron’s top strap and pulled it up over her head, before dropping the garment to the floor beside her bed.

Completely naked before him, Fluttershy wordlessly submitted to her brother’s advances, inviting him to do whatever he wanted with her… and he was all too eager to partake. Once again, she felt him caress and squeeze at her body with his hands, groping her like she was a sex doll. He kissed her all over her neck and shoulders, his warm tongue tenderly licking at her skin, which made her squirm and shudder with pleasure in his grasp. She all but yelped when he began sucking at the nape of her neck, and he didn’t stop until she was sure he’d left a purple-pink hickey mark. Then, gently holding her by the chin, he caned her head so she looked up at his gaze, and once more he started giving her a deep, passionate kiss.

She felt like she was melting in his arms, he loved it so much. The way his tongue rolled and lapped against hers, the way he squeezed her boobs and pinched at her nipples…

I’m… being dominated... She’d started out being the one on top, but the more intimate and intense their trysts became, the more she found herself being willingly enslaved to his whims. Right then and there, she was not in control. She was not a sister giving her brother sexual favors in exchange for good behavior. She was just a mare, and he a stallion--she being marked and made subservient to him, and he imposing himself upon her.

She felt like she was falling, and as much as she wanted to deny it… she loved it.

She let out a raw, gasping moan when she felt his fingers go between her legs again, and she squealed when he slid his ring and middle fingers into her pink depths.

Her love juices ran down her thighs and dribbled onto the floor like a leaky faucet as he spread her legs open, making her cling against him just to keep herself from falling forward onto the bed. He went back and forth inside her, his digits wriggling and twisting every which way as he plunged past her deep pink folds, stirring her honeypot like an actual pot of soup. As he did this, he used his thumb to stimulate her clitoris, rubbing and pressing at her most sensitive spot as he fingered her. He was slow at first, but then he started moving faster and faster inside her, plunging his digits with increasing tempo into her pussy and rubbing harder over her clit. All the while, he kept his other hand at her chest, ruthlessly squeezing one of her boobs and pinching at her bright pink nipple.

By then, she could no longer hold back her moans, and every breath she took was a wanton moan. Even when he kissed her, she whimpered into his mouth, unable to stop herself as he worked his magic on her mound. She gasped each time he shoved his fingers back up into her. “Hah, hah, hah, HAH! Z-zephy…! Don’t--Ahn--I’m gonna...!”

“Don’t what, sis?” her brother asked, grinning. “Don’t do... this?” Without any warning, he forcefully pressed his mouth against hers, and when she gave a startled, muffled gasp into his mouth, he shoved a third finger inside her, and pressed all three digits against her G-spot, whilst his thumb mashed down on her clitoris. With his other hand, he squeezed hard into her breast, sinking his fingers so far into her teat meat that they seemed to disappear.

The ruthless stimulation brought on by him simultaneously giving her the twister, digging his hand into her tit like it were dough, and forcefully kissing her, was all too much for her to handle, and she threw her head back, her body convulsing as she orgasmed, though her brother refused to let her escape his lips. She gave a smothered wail as she came, all but screaming into Zephyr’s kiss--she was so loud, that if he didn’t have her mouth covered by his, she would have probably scared the birds outside. Her knees buckled beneath her, and a small spray of her own nectar erupted from out her marehood.

All of the strength in Fluttershy’s body seemed to fade from her, only held up by her brother’s hold on her body. She felt Zephyr finally release her from his kiss, and removed his hands from her thoroughly pleasured, thoroughly abused breasts and pussy. She all but gasped for air when he did, her breasts rising and falling with each hot, raspy breath she took. Her tongue lolled out past her lips as she caught her breath, and she idly saw a small strand of saliva still connecting their mouths as he pulled away, before snapping into nonexistence. She could not see it, but a haziness had come over her eyes, her mental faculties struggling to come back from the mind-blowing orgasm she’d just come down from--and she could feel the blush on her face, an almost feverish heat blossoming out from her cheeks and radiating outward.

He… really does have magic hands… She had always been weak against him orally pleasing her. It was probably one of the reasons things had gotten so out of hand between them. She wasn’t too fond of being so weak helpless but to be brought to climax by him, but at the same time… she had never cum so hard in her life as when Zephyr would shove his fingers or his tongue inside her pussy.

Her brother was frustrating like that.

Zephyr gave her a smirk, the smug yet smoldering look on his faceboth insufferable yet undeniable all at once. His hold on her became more lax and gentle, and he wrapped the hand that had been squeezing at her tit around her waist to keep her from collapsing onto the bed then and there. Then, he took the hand that had just brought her snatch to climax, still drenched in her own marecum, and brought it up to her mouth.

“Taste yourself, sis. I want my hand clean.”

Once again, she wordlessly obeyed him, gently holding him by the wrist as she began gingerly, lovingly licking at his hand, lapping up her own love juices and tasting the sweet, slightly tart aftermath of her orgasm. She sucked at each of his fingers like she was sucking on popsicles, and when that was done, she licked up and down at the palm and back of his hand, until she had licked him clean of her juices.

He looked oh-so-pleased at her display, kissing her on the cheek in approval. “Mmm, you are so sexy like this, Flutter Butter… I love it when you’re a good little filly who does what I say.” No sooner than he’d finished his sentence than he released her entirely from his hold, all but throwing her on top of her bed. As she lay there, her backside to him as she caught her breath and trying to regain her composure, she heard him starting to take off his clothes, listening as he threw them all to the floor.

This is it… we’re really about to have sex… She was still coming down from her orgasmic high, and her mental faculties hadn’t wholly returned to her yet. Nor did her brother seem patient enough to allow her to recollect herself, as he grabbed at one of her shoulders, flipping her over so she faced up on the bed before he suddenly pounced on top of her.

Grabbing hold of her ankles, he spread her legs as wide and as far apart as he could, until they were were splayed at either side of her. She gasped when she felt something long and hard press against her vulva, its length sliding back and forth atop her mound as Zephyr climbed on top of her, cuddling her. She knew what that was. At nearly a foot long and more than two inches thick, his penis was impressively large. Whenever she’d give him blowjobs, he’d fuck her throat with that thing, often leaving her lungs burning from how long it’d take before he’d finish inside her and let her breath--she’d almost blacked out at least once when he did that.

Inside… that thing is going inside me, now… Not in my mouth… In my pussy...

He slipped one of his arms around her back, pulling her body into his, her breasts pressing into his chest as he cuddled her. When he looked down at her, their gazes locked; his cerise eyes staring into her cyan orbs, and he tenderly cupped the side of her face with his free hand. “...You ready for this, sis?” He asked simply, his voice quiet as he held her close, his face mere inches from her own.

In answer, she slowly moved her legs, wrapping them around his waist. Her consent came in a very meek whisper. “...Okay… Put it in me, Zephy...” She closed her eyes, trying to prepare herself for what was to come. She felt his hand slip away from the side of her face, and a moment later, she felt his shaft move from rubbing back and forth atop her honeypot, to lining up with her entrance.

Without a moment’s hesitation, her brother thrust his hips forward, and in less than a second he’d impaled her wet pink folds all the way up to his medial ring.

“Kyaah!!” She screamed aloud, her voice doubtlessly carrying throughout the entire house. She desperately grasped at the bedsheets, arching her back and throwing her head back as another intense orgasm hit her simply from having been penetrated by her brother. She was simply not prepared for the sensation of being so suddenly penetrated and filled to the brim by something bigger than anything she’d ever experienced down there. She could feel her vaginal walls spreading wider than she’d ever dared let them, the immense thickness of her brother’s cock stretching her lower lips into a perfect O ring.

She had expected pain, especially with Zephyr having abruptly impaled her like that… yet there was none. Not even the slightest twinge of discomfort, though the tightness of her brother inside her gave a feeling of intense pressure inside her core. Even as she came down from her second orgasm in a row, she felt only a deep, numbing pleasure--a rapture she had never experienced before. She could feel every part of him inside her: the thick, throbbing veins pulsating with raging warm blood, his flat, flared tip nudging against the entrance of her womb, and the ungodly hardness of his trunk feeling so large and tight inside her that she felt like she was about to be split in half.

He felt… perfect inside her. Like they had been made for one another in their mother’s womb. It left her all but gasping for air, her mouth agape and her tongue out past her lips.

Opening her eyes, Fluttershy could see a similar expression of bliss on her brother’s face, if not somehow even more intense than her own. His eyes were squeezed shut, his mouth also open from the sheer sensation of their copulation. “I...” he uttered, his whole body seeming to shiver from what she could only assume was incredible sexual pleasure. “I’m… I’m inside you, Sis…”

“Mm,” she swallowed, pulling up her arms and wrapping them around his neck. “W-well…? How do I f-feel…?”

“Sooo good,” he breathed, and when he opened his eyes, he looked almost like he was in a daze as he gazed back down at her. “Like, I can’t… I’ve never… I can’t even… Hooh, fuck.”

He brought his face to hers, giving her another deep, hungry kiss, which she welcomed without resistance, wrapping her arms farther around his neck to keep him close, savoring the ecstacy of their cuddling. She spoke to him between kisses, “D-do you… haah… do you regret… ahn... losing your virginity…mmph... to somepony like me?”

“No,” he replied without a moment’s hesitation. “Sorry I went in a little too fast there… I just... couldn’t hold back anymore. I’ve wanted this--wanted you--for so damn long.”

She couldn’t help but smile at that, despite herself. How long has it been since I’ve felt this loved? To be wanted by a stallion like this... Hours could have passed, and Fluttershy wouldn’t have noticed--the feeling of him inside her, their deep and sensual cuddling, and the lewd kisses they shared made her completely lose track of time. Aside from their breathing, everything felt wonderfully quiet and blissful.

Eventually, after the both of them had the time to acclimate to the pleasure, her brother broke the silence. “...Flutters? I’m… gonna start moving now.”

She nodded.

She watched him slip his other arm wrap around her back as well, pulling her body as tightly against his as possible, before he began to pull his pelvis back. She could feel his shaft beginning to slide further and further out of her sopping wet folds, making her feel empty and wanting. He all but rammed his way back into her, making her yelp in pleasure as he again shoved himself all the way up to his medial ring, his tip bumping against her cervix. She felt his balls touch against her perineum, back and forth, over and over as he brother began pumping in and out of her.

So this is how it feels to have sex with your brother…? Maybe Twilight and Applejack had the right of it... The two of them had been incredibly encouraging of her to give her brother a chance.

She found herself, moaning and breathless all over again, unable to hold back her enjoyment in making sweet, sweet love to her brother. Zephyr just felt so natural as he thrusted in and out of her, filling her in a way that she’d never been filled before. She dug her fingers into his back, finding herself loving all of it more and more as Zephyr began pumping faster and faster inside her.

Her brother grunted as he pounded inside her. “Unf! I could do this--mph!-- forever!”

“N--ahn!--no, Zephy, I--eek!--I’m not your marefriend! Wu-we’re only doing it onceeeekk!”

“What’re you talking about, Flutter Butter?” he laughed, “You’re already my marefriend! I get to do whatever I want with you! If I wanna squeeze these huge tits or that bubbly ass of yours, you don’t ever try to stop me! When I wanna slip my fingers inside this--nngh!--tight little cunt of yours, I make you squeal! You suck my dick when I tell you to, and swallow my cum without complain after I make you choke on this cock of mine!”

“Stop…! Haah, please stop saying that…! I’m, I’m only doiiiieeng it to keep you on the straight and narrow!”

“Like hell you are! Admit it, you love doing this with me!”

“Tha-that’s not truuuue--!”

He didn’t seem convinced. “Sure seems so to me! Here you are, moaning like you’re in heat while I pound your pussy and ruin you for other stallions! Only couples do that stuff! So just stop denying it and be mine already! Then we can have sex every day like this!”

She started shaking her head from side to side, futilely trying to deny the ecstacy of him saying things like that as he was all but pistoning inside her now. “Noo! We’re only doing this once!”

“I just wanna keep having sex with you, sis! And I know you feel the same way!”

Please, don’t say anymore!! She’d never live it down if she just capitulated to him like this! She had to resist, had to fight giving into his words which made her even more aroused than ever before! But… it just feels so good! It’s too much! It was like she and Zephyr were meant for each other. His cock just felt so perfect inside her, making her arch her back and dig her fingers harder into his back, her legs involuntarily tightening around his waist.

Again and again she found herself shaking her head from side to side, her efforts to deny the pleasure utterly in vain. The sex just felt too good. Too primal, too… raw.

...What? Now that she thought about it, was she supposed to be feeling this much of him? Wasn’t there supposed to be something they had to have done before they had sex?

She didn’t realize what that was until, by she chance, she gave a sideway glance to her nightdesk, right beside her bed…

Where she saw the unopened box of condoms she had brought up for just this occasion.

“U-uhm,” she uttered softly, a look of slight concern on her otherwise pleasured features, “Zephy, you forgot to--mmph?!” She was silenced by another sudden kiss from her brother, who didn’t stop humping inside her. Instead, his thrusts started picking up even more speed as he completely ignored her plea.

Her eyes shrank to pinpricks. Zephyr, you’re not wearing protection?! Nnooo!!! She had specifically told him beforehand that it was a dangerous time for her, that he had to swear to wear a condom before they had sex. But apparently, her idiot brother had forgotten that all-important part of their arrangement in the heat of the moment… as had she. I--I’ve got to get him off me! I have to get him to pull out NOW!

She tried. For the life of her, she tried. But to her shock, while her mind was racing, her body simply refused to budge. The audible, wet and sloppy sound of their lovemaking filled the room; his cock pounding into into her cunny so fast now he was virtually pistoning her now, his balls smacking into her perineum. Her muffled moans and squeals intermingled with his grunting and shuddering as their kiss became even sloppier and wetter than ever before. She could see the burgeoning strain beginning to cross her brother’s face.

He’s about to cum inside me! If he keeps knocking against my cervix, he’ll ejaculate straight into my womb! I have to push him off me, or I’ll--!!

Her legs only tightened further around his waist at the realization of what was about to happen, and instead moving to push him off of her, her hands only dug deeper into his shoulder blades, raking so hard against his skin she was sure she had left red scratches on his back.

She could only look up at her brother in disbelief. N-no… no way… my body… doesn’t want to let go… It wants this to happen…? It wants him to cum inside me…? B-but... that means--!!

A picture filled her mind, of a desire that had burned within her for such a long time; something she had always wanted, but thought she might not ever have the chance to have. Of her cradling a tiny, squirming bundle, humming the soft melody of a lullaby as she rocked it back and forth in her arms. Of her laying the little bundle in a beautiful little crib, the most angelic smile on her face as she kissed it good night.

Gazing lovingly at the baby she now realized her brother was possibly about to put inside her. No way! That can’t be! My body… my body wants…!

Her eyes rolled up into the back of her head, as all cognitive resistance completely melted away from her mind as she was made to understand her body’s deepest desire.

My body wants my brother’s baby!!!

The realization sent Fluttershy screaming over the edge, as the most intense orgasm of her entire life rippled throughout her being. Her back arched farther than ever before, and her hips pushed forward to welcome her brother’s length even further down into her depths, enveloping him past his medial ring and even further still, until he was hilted entirely inside her. Her vaginal walls clamped down hard upon his entire length, as the whole of her core convulsed around him.

That stimulation was enough to open the floodgates, as Zephyr let out a stifled, guttural groan as he pressed down hard on her lips, giving one final, powerful thrust into her inviting depths. Not a moment later, he climaxed harder than ever before, pounding his hips forward, his balls twitching as they delivered a torrent of scalding hot, white seed directly into Fluttershy’s unprotected uterus. An audible, muffled guzzling noise could be heard as his cock twitched and convulsed inside her over and over, each one sending a spurt of his life-giving seed. With his medial ring lodged inside her, and her intense orgasm causing the walls of her core to clamp down around his shaft, it allowed for no escape as his semen surged into her baby room, hopelessly filling it to the brim with hundreds of millions, if not billions of sperm… all searching for an egg that they would surely fertilize.

Yet Fluttershy was in no condition to do anything but revel in the afterglow, as her core continued to clamp down on Zephyr’s cock, and her thoughts was rendered a complete mess from the mind-blowing intensity of her orgasm. She let her arms and legs slip from around her brother’s body, before she fully collapsed onto the bed. This broke their kiss, leaving her breathless and all but gasping for air as she lay there. Also breathing heavily above her, Zephyr had a dazed look on his face, sporting a big, stupid, almost delirious grin as he finally managed to pull out of her, his cock soft and flaccid after finally unleashing the load that had been pent up inside him.

Rolling off of her, he also collapsed onto the bed right next her, catching his breath as he lay beside her.