Taboo

by DeWitt-Enterprises

Rating: mature
Tags: Shining Armor, Sex, Twilight Sparkle, Anthro, Profanity, My Little Pony: Friendship is Magic, Alternate Universe, Porn, Fetish
Length: 4971

You shouldn't fuck your super-sexy sister. Unless she wants you to fuck her. You still probably shouldn't, but we're here for a good time, not for a long time.

Incest is bad.

It's amoral, it leads to birth defects if there's pregnancy involved, and it's frowned on by so many people.

But... she is stupidly fucking hot.

And... she promised she wouldn't tell anyone else.

One time isn't gonna hurt...

Right?

Cover art is done by Php141 on Derpibooru

Kinks: R63, incest, Amazoness, femboy, foreplay, oral, ass-worship, analingus, excessive cum, cum inflation, enormous male endowments.

Published 2019-02-18 03:10:01 UTC
Last updated 2019-02-18 03:10:01 UTC

Incest is Wincest

"I won't tell if you don't..."

The sentence echoed in his mind, his shocked into silence, unable to say anything or move. His eyes fell on his older sister, an aroused glint in her eye as she stuck the tip of her tongue out. A light, playful gesture... one not befitting of even half of the weight of what she had just suggested.

"Gleam... I... that's not..." Dusk stammered, heart pounding in his chest as his stomach tied itself in knots.

"What's the matter?" she giggled, batting her eyelashes at her flustered younger brother. "Are you trying to tell me you don't think I'm pretty?"

She placed her hands on her hips... her full, wide hips... as she looked down on him, the older sibling standing easily a foot taller than her little brother. He shifted awkwardly, looking as if he were ready to bolt out of the room the second she moved again, eyes wide in horror and mouth still agape in shock.

"I don't think we should... do you have any idea how much trouble we'd get in if anyone found out?" he asked.

"That's why they won't," she winked. "We've got no prying eyes, no one else in the house, and no reason for anyone to find out unless one of us says something. And like I said before: I won't if you won't."

"I can't believe you're making this out to be no big deal," Dusk spluttered. "Do you have any idea what you're suggesting here?"

"A little bit of casual sex between two horny friends?" Gleam asked with a wide, uncaring shrug. "We're both adults, both aware of what doing the nasty is. I don't see what the problem is."

"The problem is that we're both related!" Dusk barked, his fear switching to fury for a moment. "How do you not see that?"

"I do see it, you dumb-ass," she sniggered. "I just don't care. And besides, it's not like I'm asking you to marry me and move us to a farm out in the country. All I'm asking for here is an hour or two away in the bedroom to help take the edge off."

"I don't have an edge to take off," Dusk growled.

"Oh, that's a load of shit and we both know it," Gleam scoffed, jabbing a powerful finger into her brother's petite chest and eyeing him up. "You've been dragging yourself around in every position you could think of to try and hide that raging erection of yours from me. I honestly can't believe you even think you're successful with it. I honestly think you should be more ashamed of how bad your hiding skills are than the fact you wanna plough your big sister."

"I don't want to-" Dusk began, eyes alight with fury before catching himself, calming down with a sigh as he continued. "I don't wanna plough you. It's just a perfectly natural reaction to the fact you keep walking around looking like... like-"

"A fine piece of ass," Gleam giggled, slapping herself on her voluptuous backside.

The jiggle of her cheeks was visible even while standing in front of her... her booty was just that big. Tiny, blue PT shorts barely long enough to hide her pussy were filled up enough to split around that alabaster ass, seams screaming in agony every time she bent over.

The rest of her attire didn't help much either; a long-sleeved crop top as white as snow, cut off at the midriff and barely able to hide the titty or muscle that made Gleaming Shield steal the eye of every person she walked past. Each breast easily larger than her head, rippling muscle up and down her stomach trained and worked hard enough to grate cheese on, strong arms and powerful shoulders.

Gleam could pick Dusk up and snap his twink body like a twig between her fingers... and he'd probably thank her for that.

"Like some kind of skank!" Dusk yelled.

"You complain..." Gleam chuckled, eyeing up her brother's crotch once again and noticing the very prominent bulge against his thigh. "But the big guy down there seems to really like the way I dress..."

"It has nothing to do with you," Dusk said, a blush touching his cheeks as he looked away from her. "It's just a natural reaction to the presence of someone as... someone who is..."

"As fuckable as me?" she finished for him.

"Will you stop that already?" he growled.

"Hey, sugar, you're the one popping stiffies over your big sister," she said with an arrogant wave of her hand. "I'm not the freak for wanting to lend a hand... or a pussy..."

Dusk went to speak again, but Gleam cut him off. She grabbed hold of the scruff of his shirt and lifted him up into the air. She pinned him to the wall, finally having him face to face at her staggering height of six-foot-six, and grinning smugly at him. Dusk's face was one of horror, scared to the core and unsure of what was about to happen.

"Here's the thing I'm wondering, lover-boy... if you're so confident in your rockhard cock being 'just nature' and that it's got 'nothing to do with me'..." she wound up. "Why not just fuck me platonically? Why can't you just forget I'm your big sister and enjoy me for me?"

"Because it doesn't work that way!" he growled.

"Sure it does. I know how stallions work. Especially pent up little virgins like you that haven't so much as inhaled air in a room next to exposed pussy since the day you were born..." she started. "You angry little virgins are so fucking desperate, that you can't control yourself the second you get the taste. Once that dick gets hard and you start thinking about plunging it ten inches deep in the nearest, wettest, tightest cunt... you go full retard."

"Gleam..." Dusk growled.

"No sensible thoughts, no holding back, no moral code... it's just you and whatever you need to cum, that's all that matters," the enormous mare continued. "So why don't I tongue-fuck your mouth until you're so horny that you can't even think straight... and then you tell me about all the things you're gonna do to this pussy?"

"Not a chance on this Eart-" he began before his sister locked lips with him.

The mare dropped him at first, then catching him in her arms as she pinned him to the floor. Her size and weight was nearly twice his own, her natural strength being more than he could ever hope to achieve as her large, powerful hands pinned his girly little chest to the floor.

Her tongue his the back of his mouth instantly, her superior size being arousing on its own to the whipped little beta-male, but having something that big, that hot, and that nimble in his mouth seemed to melt a few wires in his brain. Then came the moment when she removed her hands, squishing her enormous tits against Dusk's petite chest and continuing to squash him under her goddess-like body.

His cock was now throbbing hard enough to hurt, being able to physically feel pre-cum dribbling out of the tip and staining his underwear as his sister broke his resolve. Dusk's hands seemed to go wherever the wind would take them, clapping them against his sibling's enormous ass with a thunderous slapping sound. His fingers dug in, sinking into her bouncy backside as it shook with the impact.

An impulsive, instinct-driven growl was drawn from Dusk's lungs, sliding over Gleam's tongue as she tore away at her brother's jeans. Her fingers closed around his cock, the shredded remains of the clothing being cast aside, as she began to pump her hand up and down his enormous length. She marvelled at the size of his dick, thick enough to almost struggle closing her fingers around and long enough to bury itself well over a foot inside her before even reaching the tip.

Her eyes lit up with excitement, feeling Dusk's abundant pre bubble out and over her fingers as his cock drooled at her touch. She broke away from him, eyes glowing with unending arousal and a naughty smirk plastered on her mouth. They were both panting, chests heaving up and down in near-unison as they pressed up against one another.

"So..." Gleam asked in a lascivious growl, eyeing her brother up hungrily. "Shall we take this to the bedroom?"

Dusk's eyes darted sideways for a brief moment, the conflict plain as day on his face before his purple orbs screwed shut. A heavy sigh fell from his lips as he stared into Gleam's eyes once again.

"You'll make it good?" he asked.

"The best you'll ever fuckin' get," she promised.

"Then help me up," he answered, voice growing serious. "And don't you dare tell a soul about what we're gonna do."

Gleam launched her brother onto their parent's bed, the small stallion landing decently comfortably before Gleam began to strip down. She tore at her clothing, ruining her shirt, shorts, and panties as she cast them aside. She grinned hungrily at Dusk, tensing her strong, toned body for a brief moment and exposing every ridge, bump, and sinew on her soldier's form.

Dusk gulped audibly, a mix of fear and arousal coursing through him as he wondered if the sex would be worth the bruises. Gleam strode over to him, placing her hands to his chest and slamming him down into the bed. Once he was ready and terrified, Gleam dropped her enormous ass right on top of his face, the sheer size of it forming an almost air-tight seal around his head as she began to grind circles on his mouth.

"Give it a kiss, gayboy," she said with a teasing smirk, flicking Dusk on the thigh as she wrapped her other hand around his cock. "Make me feel good and I'll do the same for you."

Dusk's entire being tensed as both of Gleam's hands wrapped around his twitching shaft, still slick with cum and only pouring more as his sister worked her magic.

"Gods, who'd have guessed such a girly thing like you would be packing a cock like this, eh?" Gleam teased, rubbing the tip of Dusk's cock with the palm of her hands, teasing him with her touch. "Dig in, Dusky... and I'll let you cum."

The gasping femboy did as instructed, plunging his tongue into his sister's asshole with nary a sense of restraint. His fingers dug into the alabaster flesh of her ass harder than before, nearly losing his hands in her enormous backside as he kneaded. Gleam's back straightened briefly, a loud moan pouring from over her tongue at her brother' surprisingly-skilled approach to his work.

"Talented tongue you got there, honey," she sniggered, fingers reaching down to her brother's enormous balls as she spoke. "Keep that up and I'll blow your load good and fast."

She curled her fingers around one of his balls, the apple-sized nut sitting in the palm of her hand, the leathery flesh around it drooping and pooling in her fingers as she rolled his ball around in her grasp. She bit down on her bottom lip, excitement bolting through her as she became more and more acquainted with her little brother's junk. His cock seemed to love the attention, his balls next in line and just as happy...

Only one other place to check, it seemed.

Gleam lowered her fingers further down, over his balls and between his big, girly ass. Her fingers wasted no time, pressing against his puckered backside before going all the way in. Gleam cast an eye over her shoulder at her brother's sudden moan of pleasure. He made no request to remove her fingers, made no attempt to resist her touch. He instead hardened his licking, putting more and more pressure into lapping against her spit-slicked asshole as he buried his muzzle harder into her cheeks.

"Seems to run in the family, doesn't it?" she giggled. "Both of us like it up the ass? Good to see we have something else in common, baby brother..."

Gleam pushed her fingers deeper inside him, his tight cove eagerly swallowing them as she reached his own pleasure buzzer, fingers rubbing against his prostate in a soft, gentle manner.

"Want me to make you cum like this?" Gleam chided, sticking the tip of her tongue out. "Does the little femboy wanna get off from his big sister's fingers up his ass?"

She felt Dusk nod, nod vigorously, against her ass, hips bucking forwards against the hand still rubbing his cock. Gleam smirked cockily, shrugging her shoulders as she slid her hand down from the tip to the middle of his enormous shaft.

"Alright then," she chuckled. "Get ready."

The elder sibling was not slow. The elder sibling was not gentle. The elder sibling gave Dusk a hard fingering, ramming them in and out of his tight asshole, rubbing his prostate with the flat of her fingers, all the while bombing her hand up and down his shaft. She could feel the buxom little girly-boy twitching underneath her, could see his thick thighs tensing and quivering, the sensation of his fingers digging hard into her ass as he continued to ream her own wet asshole.

Dusk was spurting pre at this point, his excitement and his virility creating quite the mess. White pre-cum slopped down his shaft, staining the bed sheets beneath them, coating Gleam's hand, and being flung everywhere with the speed the mare was stroking at. She could feel the burn start up in her arm, the strain in her fingers as her little brother's stamina proved itself to be more than impressive, managing to last for a good, long while before he eventually came.

And cum he did.

Dusk locked up the second his orgasm hit, firing off a shot that would've blinded Gleam if it had hit her in the eyes. It slopped against her forehead, hot as lava and thick as glue, with an audible splattering sound. It happened again and again, Gleaming keeping her eyes closed and her mouth open as Dusk's monster cock fired off more and more ropes of hot, steaming cum.

Gleaming soon found herself soaked, coated almost head to toe in spunk, that warmed her through to the core. The sensation was almost therapeutic for her, the warmth of the coating feeling somewhat relaxing for her muscles, only distracted by the smell. It wasn't a repulsive scent by any means, nothing that made her turn her nose up.

But it stank of masculinity. The stench only a real alpha stallion could produce, thick and heavy, catching in the back of her throat with every breath. It got her hot under the collar and brought a heat like no other between her thick, strong thighs. She removed herself from her brother's face, seeing the flattened twink panting and gasping in an exhausted manner as she sat on her haunches, hands crossed over her cum-soaked tits as she stared down at him.

"That was quite the splash, dickhead," she said with a teasing grin. "You always make that much of a mess or am I just that much of a turn on for you?"

"I wanna eat your pussy..." Dusk said in an almost pleading tone, eyes wide and genuine with desperation.

"The desperation is appreciated," Gleam nodded, smiling down at her little brother. "But I think you'd best get some air in your lungs after that."

"T-Thanks..." Dusk commented, resting on his elbows.

"So..." Gleam began. "How're you liking it so far?"

"I..." he began, eyes falling downwards for a brief moment before looking back up at Gleam. "You feel incredible."

"Whaddaya like about me?" she smirked, posing with her arms held above her head, showing off her enormous breasts, wide hips, and thick thighs. "What really gets your cock throbbing?"

"Your... your ass," he answered, cheeks flushing red again.

"No love for the twins?" Gleam asked, clapping her hands to her tits and bouncing them gently. "Every third guy I meet says he can't keep his eyes off them."

"They don't really... do it for me," he shrugged.

"Ah, an ass man through and through," Gleam nodded slowly, lowering herself onto her back and spreading her legs, parting her cunt with her fingers and sticking her tongue out. "Oh well... come and get it."

Dusk nodded hungrily, crawling over on his hands and knees to his sister's treasure trove. He buried his face between her legs with no hesitation, the heat radiating off her tight, sweet cunt nearly melting his brain out of his ears. A long, slow lick of her folds sent a bolt of lightning through Gleam's body. Her hand gripped tight at the back of Dusk's head, toying with the long ponytail he kept his mane in.

His tongue slid over her once again, this time with much more pressure, parting the wet slits and delving just the tiniest bit inside her cavern. Gleam's legs tensed, toes curled against her feet as another, much harder shudder ran through her body. Dusk placed his hands against her thick thighs, squeezing gently as he repeated this same kind of lick, over and over again he lapped and drooled against his sister's sweet, heavenly pussy.

Gleam leaned back against the headboard of the bed, breathing as deeply as she could with the occasional sudden bolt of pleasure causing her to gasp, bite down on her lip, and tremble. Dusk had quite the talent for licking, she noted. Whether he was burying his tongue in her ass or delving deep inside her dripping cunt, her tiny little sibling had a knack for bringing wave after wave of pleasure onto her enormous form.

Dusk's licking eventually went more aggressive, truly burying his mouth in her pussy, driving that thick tongue as deep in her as it would go, all the while rubbing and stroking her clit with the tip of his thumb. This sent an entire lightning storm of pleasure through Gleam, toe tip to ear tip trembling in bliss, chest heaving up and down as the tiny twink worked magic on her pussy.

She could feel her own lady lube pouring down onto the bed, her pussy drooling from the A-one treatment she was receiving. As soon as she even mentioned it, Dusk went on the hunt for every drop from her cunt. His tongue attacked her clit, her lips, and even her thighs. He kissed and suckled her pussy, his muzzle soaked down to the bone in a matter of minutes as he continued to devour her tight snatch.

"A-And where exactly did you learn to do this, eh?" Gleam demanded, gently pressing Dusk's face deeper into her cunt.

The response was nothing more than mumbling from a mouth stuffed with pussy, so Gleam decided to take that as his final answer.

"Good to know," she shrugged, rolling her shoulders briefly before settling back down into a more relaxed state.

She wasn't gonna last much longer, that was more than obvious. Her breath was coming in hard, heavy pants, her cheeks burned about as hot as the surface of the sun, and her cunt felt like it was ready to burst, the build up inside her pussy being almost too much to bear. She could feel herself riding just along the edge of an orgasm, biting down hard on her lip as Dusk's last few, final licks, stroking good and deep inside her, shoved her good and proper over the edge of euphoria.

She clapped her hands to his head, once again shoving his muzzle against her cunt, as the floodgates opened, spilling her lady-cum down onto his tongue, pouring it into his mouth, and coating his muzzle with her honey. The purple stallion pulled back, leaving his sister as a twitching, quivering pile of pleasure as he licked his chops clean.

Gleam settled soon after, regaining her composure and sitting up properly, her cheeks stained with the red heat of debauchery and her tongue hanging from her maw, a look of pure pleasure on her face. Dusk crawled over to her, pressing himself against her enormous body, wrapping his arms around her neck, and kissing her passionately.

His tongue slid back over hers, electricity crackling through them on contact, the sweet taste and the warm embrace they shared together managing both to settle and excite the other. They broke apart, eyes locked in a passionate stare for the longest moment, neither willing to blink or look away.

"Ah... this has ended up being a lot more wholesome than I expected it to be," Gleam said, snuggling her brother against her enormous bust and resting his head on her shoulder. "Dusk... mind if I make a request?"

"Uh... go ahead," he nodded.

"I know you haven't hit it properly yet... but d'you wanna make this a regular thing?" she asked, looking down at him.

"I... I think I'd enjoy that," he said with a slow, warm nod.

"That's good to hear," Gleam giggled, a flash of evil appearing in her eyes. "Now... rut me."

Gleam's confidence was soon wiped away from her face as her brother tackled her down onto the bed. A sudden burst of strength, through magic or breeding desire, allowed Dusk to break the hold she had on him and spread her thick thighs good and wide. The tip of his fingers lit up with a brilliant purple aura, tracing a single just above the entrance to her cunt with trained expertise, finishing it off with a gentle slap of her labia.

"Ow," he commented in a dry tone, eyes looking down at the strange symbol. "And... exactly what is this?"

"Contraceptive spell," Dusk said with a firm grin plastered on his feminine features. "I'm not pulling out and I'm not in the mood to raise kids with you."

"I agree with both of those statements," Gleam nodded, watching as Dusk lined himself up against her entrance.

It was only when compared to her wet slit, even for a mare of her size, did Gleam truly comprehend how monstrously-huge Dusk's cock was. Ponies were made to take big dick, it was in their nature... and yet a slight tremor of fear ran down her spine as she beheld the beast her brother kept locked in his pants.

"You'll be super gentle and romantic, right?" she asked, batting her eyelashes playfully.

"No," came the dry response.

"Eh, worth a shot," Gleam sighed with a dismissive shrug. "Let's put me in the hospital!"

With a guiding hand and mighty thrust of his hips, Dusk rammed his cock down to the base inside his sister, smashing past her cervix and hitting the deepest parts of her womb. Gleam threw her head back with an almighty moan of pleasure, cracking the wooden headboard on impact as her legs wrapped around Dusk's wide hips.

He pressed his hands to her enormous tits, groping them with enough force to make the pleasure painful... and the pain pleasurable. Gleam's eyes rolled back almost to the white before Dusk's girly hips even got going. With a grunt, he kicked himself into gear. Pussy-destroying cock pulling back and ramming inside her over and over again. Every inch of his cock, thick as an arm, nearly splitting Gleam's tight cunt wide open every time his hips so much as moved a half inch.

Her mind was in wonderland at this point, tongue hanging from her mouth and drooling a pool of thick, scented saliva onto her collarbone. Dusk had really woken up his alpha side when the chance to fuck came about, as the previously-meek and timid femboy had now transformed into some kind of breeding god.

She could feel him leaking into her pussy, already pouring enough cum to get her pregnant were she not protected by that spell. As much as she'd come here for a quick and hard fuck... the concept of having her brother cum inside her, the mental image of millions of sperm battling and rushing to fertilise her eggs... being bred like a prized farm animal by her own little brother.

It brought a shiver to her spine and a wave of debacherous lust in a way she didn't think possible. She felt full already, Dusk's hyper-virile cock having already filled up her womb with his pre cum, not even a quarter of a way to an orgasm before she'd been thoroughly filled. She could hear his cock slopping against a cum-filled cunt, the vulgar sound charming her like the most beautiful piece of music she'd ever heard.

Dusk leaned forward and kissed her, suckling her tongue gently as his hips continued to slam against hers, the loud, hard clapping of flesh smacking together adding to the already-angelic harmony of moans, squelches, and groans coming from the both of them. Dusk broke away for a quick moment, lapping up the saliva Gleam had drooled on herself before locking lips with her again.

Her arms wrapped around his neck, holding him close to her body as he continued to grope her tits. His fingers sunk into her white bosom, there being more than enough tit to satisfy four of him, slobbering against his sister's tongue, pounding her cunt, and really losing himself to a building desire to cum enough into her to full her up five times over.

Her pussy hurt. She was being stretched to capacity, getting fucked so deep that she was sure not even air had touched her that far inside before. Her brother, her teeny, itsy-bitsy little twink of a sibling, was currently giving her a fucking so hard that she'd more than likely be unable to walk for a solid week afterwards. Sweat coated her body, the exertion of getting dicked that fucking hard working up a sweat the likes of which she hadn't seen in a while.

Dusk's body was working overtime, she could see that much just from looking at him. The muscles, or what passed as muscle on the curvaceous little babe, were taut, twitching, and flexing at capacity. His desires were clearly overriding his exhaustion, and though his chest heaved hard and fast and his muscles were no doubt aching, he didn't slow down in his quest to fuck his sister's skull off her spine.

Dusk's hands slid up to Gleam's throat, clenching tightly around them and slightly cutting off her air supply. Though unbidden, Gleam had literally no complaints about this. If she was gonna get dommed by her little brother, she might as well go all the way with it. Choked, slapped, and spat on, it didn't really matter at this point. She felt better right now than she had in fuck-know's how long, and a little bit of abuse wasn't gonna do anything except make her cum harder.

And speaking of cumming harder... Dusk gave her an orgasm she wasn't gonna forget for a long time.

His thrusts became shorter, really getting into his rut as he continued to pound her faster and faster, barely using more than the first six inches of his cock to fuck her before he seemed to hit his own big time. With a loud, almost-comedic whinny, Dusk came inside his big sister, the first stream of cum being enough to make her belly visibly bulge from impact alone.

The little girlyboy came more in two spurts than most other species came in an entire year, mouth locked against his sister's as his cock started and just didn't stop. He sprayed blast after blast inside her, glue-thick spooge packing in tighter and tighter until Gleam's belly began to balloon outwards. She grew larger and larger, the thick cum inside her sloshing and gurgling as it continued to stretch her taut stomach even larger. She looked pregnant in less than a minute, her stomach almost glowing with the heat of the load still being blasted inside her.

Dusk pulled out of her cunt, the alabaster mare expecting that to mean he was done with his orgasm. Goodness gracious, was she wrong. Dusk's face tightened even harder, a second wind the likes of which she'd never seen as he continued to stroke his cock. His fingers were soaked with cum, both hands milking his dick for every drop he had as he continued to cum all over Gleaming Shield.

The bed sheets were soaked, the headboard stained, and even the wall above the bed had taken a new coat of paint before the sperm-god femboy finally sputtered out, dropping into the embrace of his cum-soaked sister. He smeared purple coat with his own load, an audible slop sounding as the two made contact... but neither of them care.

Gleam's bulging belly remained tight and full, even as he began jetting cum out of her cunt, adding to the already enormous pool of it on their parents' bed. She cradled her brother against her body, kissing him once again as the rapturous feeling of orgasm wore off and the soft, warm, post-sex haze of exhaustion and content washed over them both.

Their breathing soon settled, blushes faded away, and words found their back to their lungs after several minutes of sitting together, covered in a load of cum that seemed to never lose it's heat.

"Gleam?" Dusk asked after a quiet moment.

"Yeah, baby?" she asked, looking down at her spunk-stained sibling.

"Can you bring Cadance next time?" he asked, back to his innocent and timid demeanour after he'd clearly cum out all of his bravado.

"Yeah... I think I'll do that," Gleam said with a curt nod and a wide smile. "Now... we'd probably better clean all this up before mom and dad get home on Monday..."