Knocking Him Down A Peg

by Deus Foalt

Rating: mature
Tags: Alternate Universe, Twilight Sparkle, My Little Pony: Friendship is Magic, Fetish, Shining Armor, Porn, Sex
Length: 3827

Twilight has a plan to knock her brother down a peg in the sibling pecking order…

Twilight Sparkle and Shining Armor have always had a close relationship, more than just brother and sister. That being said, aside from the family ties involved, their relationship is very…vanilla. Twilight hopes to change this, so she leverages a long-lost childhood keepsake, the coveted title of Sibling Supreme, and a favor from a friend in exchange for her brother’s willingness to try something new. How does this situation play out?

Sexily.

This story takes place in S4 before Sparkle’s Seven, and serves as a sort of alternate outcome as to who gets to keep the helm. Tagged AU because this would totally change the dynamic of said episode.

Written for the 2022 Incest is Wincest First Time February Contest. Pre-preread by AndwhatIseeisme and CrimsonSoldier. Preread by LilSlipsy. 

Contains: Incest, pegging, anal, F on M, mild power play, sex toys, the hard-won helm of the Sibling Supreme, Shining being a bit of a dork, and hip pinball-esque games.

Covert art by imadeus, no relation to me whatsoever. Derpi 2794203

Featured on 2/11. Thank you!

Published 2022-02-11 03:40:01 UTC
Last updated 2022-02-11 03:40:01 UTC

Peg T Fits In Slot S

Twilight Sparkle tried her best not to bounce up and down on the edge of her bed, to a limited degree of success. Her big brother was coming over, and that was enough to send her heart skipping about in joy, and her lips to crank out endless giddy smiles. But she had many more reasons to be excited. Namely, the…surprises she’d borrowed from Fluttershy.

Fluttershy’s ‘stash’ was on a need-to-know basis, but Twilight managed to convince her that she’d make very good use of the items she borrowed. After all, she’d just read about a fun new phenomenon in Ponyville Mares Monthly, and wanted to try it out on good ol’ Shiny. Of course, Shining would need some persuasion to cooperate…and that was where one of their childhood keepsakes came in.

The last she remembered, Shining Armor had the crown belonging to the Sibling Supreme. Sure, it was just a bit of painted cardboard, paper, and other flimsy materials, but it represented the best of the two. Shining had taken it when he left all that time ago…and she never got to try it on again. She didn’t consider herself to hold very many grudges, but this was definitely one of them. In any event, this was going to be her chance. Twilight had sent off a simple letter with a drawing of the crown, and very succinct instructions:

Come alone. Come prepared. Knock twice, then once. Lock the door behind you. -XOXO

Their relationship as a bit more than just brother and sister was about half as old as the crown of the Sibling Supreme was…and what better time to unite the two traditions than on the anniversary of their first full-blown, blushy, messy kiss? That was today! She could only hope that Shining hadn’t run into any delays on his way down from Canterlot…at least Fluttershy had also agreed to watch Spike for the whole night, given the nature of what Twilight had borrowed. They’d have all day and night to settle this.

Knock knock…knock

“Come iiiiiin~!” Twilight trilled, eagerly swishing her tail behind her as she stood up on all fours, and trotted to the edge of the loft containing her bedroom. Her eyes stayed glued on the door as it first opened one inch, two…and then all of the inches. Shining Armor stepped past the threshold and quickly shut the door, locking it behind him as he’d been instructed. Having done so, he then turned his attention upwards, and that was when she saw it, a glint of gray: the crown! He was still wearing it even though he’d just happened to win the week that he left? Twilight had to suppress a growl, and did so by making the widest smile possible. Easy, Twilight. You’ll get the ultimate status symbol soon enough.

“Twily!” called Shining, his self-assuring smirk only falling slightly when he came upon his sister’s wild grin. “Y’know, it’s been so long, I almost forgot about—“

“Why don’t you come up here first?” Twilight interrupted, patting the side of her bed as her eyes flicked towards the stairs. “We’ve got some catching up to do, and I don’t think half-shouting across the library’s going to work very well.”

“Fair enough!”

Every clip and clop of her brother’s hooves on the stairs only intensified Twilight’s excitement. Finally they were together again. Oh, the things they would do…

“So as I was saying, I—mmph!” Shining initially recoiled as he was interrupted by Twilight zooming over to him and kissing him, but soon leaned into her and did a deep sort of purr low in his chest. Twilight smiled as much as she could while still locking lips with her BBBFF; she missed that sound, she missed this. His warm lips, his strong frame pressing forward to take control…a hoof coming to rest on her back…

But not tonight. Twilight broke the kiss before it went any further, as well as the string of saliva that remained behind, linking their lips. “We have plenty of time to be lovey, big bro. But first comes…the crown.”

“Yeah, this old thing!” Shining tapped a hoof on the cardboard construction, smiling wistfully as he did so. “I almost forgot about it ‘til your letter reminded me. And since I won it last, I figured I’d wear it for my visit. How do I look?”

“Like a million golden stars,” Twilight responded through tight teeth. “But tonight, I bring you a difficult challenge…” The alicorn flopped back down on her bed and spread herself wide open, giving her big bro quite the lovely display. Then she rolled over and onto the edge of her bed again, patting next to her to urge Shining to sit. He did so after a moment’s hesitation…Twilight knew he’d been staring. But that was exactly what she wanted. “Tell me, Shining…how adventurous do you consider yourself to be?”

“Uh, a fair bit? I am a Captain, you know.”

Twilight rolled her eyes, before laying a hoof across his shoulders. “I meant in bed.”

“Oh, uh…” Shining’s face began to turn red; no doubt he was recalling nights with his wife. Twilight decided to cut that short; his conscience sometimes got in the way of their fun if given too much room to roam. Even in an open relationship, Shining was very…traditional sometimes. Their first time together had even been in a very awkward missionary position, laid across his bed and trying to be quiet enough that mom and dad in the next room over didn’t wake up. So anything not traditional was…not often on his radar.

“Have you ever heard of…pegging?”

Shining arched an eyebrow. “Isn’t that the new pinball machine everyone’s going crazy about for some reason?”

“Not Peggle, pegging.” Twilight huffed, before magically pulling out her issue of Ponyville Mares Monthly and flipping to the page that first gave her idea; the very first one in the ‘after dark’ section. She handed the magazine to him, and let him read for a bit before she continued. “Basically…I’d be the one on top, giving you a good rutting.”

“I dunno Twi…” Shining said, his cheeks coloring the more he read about the practice. “I mean, Caddy floated it once, but…it kind of gives me the shivers thinking about anything at all going inside me from behind.”

“So the crown’s mine, then?” Twilight could practically feel her eyes sparkling as she looked over at Shining. His uncertain frown turned into one of determination. She suspected he’d do anything to keep the crown…and her suspicions were confirmed as Shining sighed and turned to Twilight, slouching a bit as he tossed the magazine aside.

“Fine,” he relented, crossing his hooves. “So in exchange for letting you rut me for the first time, I keep the crown. Is that right?”

“For a whole month! And just about~” Twilight teased, drifting the hoof on his shoulders lower as her voice lowered into husky undertones. That he was even letting her do this was indicative of just how much he still treasured it…even though he forgot about it. Typical Shiny. “But one more twist. If I can make you cum just from pegging you…I earn the crown if I so choose.”

“Fine by me, Twily,” Shining said, rubbing the back of his head. “Don’t think I will, but consider it a deal.” He looked towards Twilight’s crotch as he did so. “But uh, how are you gonna…”

“Oh dear big brother, did you even read the magazine?” Twilight’s voice dropped into her most husky register as she retrieved the magazine and placed it back on the table closest to her window, all without ever leaving her seat. She stayed there to trace a hoof gently down his chest, not stopping until she hit the prize. He was still sheathed, but a little poking and prodding had that become less true with each passing second. “I mean, I could use magic to give myself something to work with…but I think magic has no place in a contest between us. It’d be a bit unfair, after all; somepony with magic as their cutie mark versus a guard?”

“I’ll have you know we guards are very magically competent.” Shining huffed, but he was still shivering and blushing at his sister’s constant attention to his cock. He was clearly enjoying the game, and obviously she was, too. So she went along with it.

“Of course, you’re Equestria’s Finest,” Twilight purred, before shifting her rump just a bit further away. “But I still say there’s no substitute for practical alternatives…like this!”

Twilight’s horn lit up, and her smirk reached critical wideness as she levitated something out from under the bed, directly beneath their dangling hind legs. First came the network of sleek black straps, with a trio of butterflies covering an intersection—Fluttershy’s personal touch. Next came the large artificial phallus attached to the center of the straps; it was purple, rubbery, and big. Twilight giggled as she watched her brother look first at his own fully-erect self, and back at the toy, and realize that he was smaller than it. Only by a bit, but enough that they both noticed.

“Don’t worry, I don’t expect you to take this without some help…” Twilight murmured gently, leaning in to plant a kiss in the nape of his neck...one of his favorite spots. Her magic, while busy securing the straps of the strapon around her hips, tugging and pulling, also brought up a bottle of lube for Shining to stare at.

It was only a matter of seconds before Twilight felt the final strap tighten, and the sheer weight of her new appendage pulling down towards the ground. Twilight followed it somewhat, but only to give her brother’s member a good lick…and then another for good measure.

“Ah, T-Twily…!” Shining Armor grunted, grabbing the edges of the bed as he bit his lip.

“Just oooone more thing, big bro,” Twilight whispered as she planted a kiss on his twitching shaft. “I don’t want you to make too much noise; I do have neighbors. So…here!”

Before the stallion could even do a thing more than open his mouth, he found himself interrupted as a red ball flew out from under the bed and wedged itself into his maw. A flurry of straps followed behind, quickly wrapping around his muzzle and behind his head, sticking into place as he tried to spit the ball out, but failed. The look on his face said he definitely had not expected to be gagged. Twilight humored him with another lick to his cock, pulling the head strap extra tight before snuggling up next to him, letting her fake purple phallus brush against her brother’s hind legs.

“I’m not a mare with no heart, so I will give you a safeword,” Twilight informed Shining as he mmphed unintelligibly into the gag. “If you wanna stop at any point, just tap three times with your right hoof.” Twilight demonstrated with her own leg. “I’ll stop, but know that the crown will then be mine. Fair?”

Almost immediately, there came two taps from Shining…and then a hesitation. Second after second hung in the air. Twilight used the time to squirt a fair amount of lube onto her penetration tool, and spread it evenly around with her magic.

Eventually, Shining actually nodded, and a muffled “fhr,” emerged from his throat. Yes, he was on board!

Twilight felt her smirk nearly escape the bounds of her face as she stood up on her bed, her new toy swinging heavily between her legs and tapping the very bottom of her chest. Gently, but not too gently, Twilight shoved Shining’s shoulder, encouraging him to flop over sideways. “Assume the position, big bro, so the contest for the hard-won helm of the Sibling Supreme can begin~”

Shining complied, rolling over onto his stomach, perching his rump in the air and allowing Twilight to climb on top of him. As she did so, the purple phallus fell between his hind legs, nudging its way past the back of his tail, and into the cleft of his rear. Twilight could see her brother’s back shaking slightly as he held himself in place, as if the mere position gave him anxiety.

“Remember, you’re not allowed to cum, big bro,” Twilight teased softly, pressing the tip of her dildo against his entrance. "But I would encourage you to relax. It’ll make things easier on both of us. Are you ready?”

“Mmmm…mmmphm.” Shining’s response was clarified with a nod of the head. He mumbled something after it, but the red ball pinning his tongue down reduced his complaints and smug side-talk to gibberish…just as Twilight liked it. She leaned forward, her lips brushing against his ears, and whispered into them.

“Good. Then let the games…begin~”

Twilight lightly bit Shining’s ear as she pressed the large shaft against her brother’s puckered tailhole, and slowly began applying force with her hips. After a bit of resistance, she slid in, smooth as could be expected. If there was one thing Twilight had learned about anal on her own, it was that too much lubrication was not a thing that existed. And so even with a virgin tailhole like Shining’s, it was easy to glide the first few inches in. The next few were met with resistance, but that was okay; she’d break that down in time.

Her brother snorted through his nose as she continued; her first few thrusts were slow, short, gentle, just enough to get a sense of what her new toy felt like in there. Shining whined and wiggled at first, but it seemed like the longer she stayed in, the less resistance she was met with.

But that wasn’t quite the result she was hoping for…she wanted resistance, she wanted to win the crown. So Twilight began deepening her thrusts bit by bit, leaning more of her body weight onto Shining’s back as she went. She could feel his muscled body jerking with each push, and hear the adorable little sounds he made with every bump:

“Mmph…mmph…mph…hmph…”

“That’s right…” Twilight drawled, thrusting slowly deeper and deeper. This strap-on was unfortunately not one that had a piece that went inside her nethers, but she could feel the sexual energy radiating from her hindquarters, coming from deep within her chest as she utterly dominated her big brother. “Feel me, feel me good…feel your big sister reach deep inside you.”

Twilight smirked as she pondered her pun briefly, before an idea hatched. Her thrusts were already as deep as they could be, so Twilight sped up, enjoying the thwap of her thighs against her brother’s toned butt with every thrust as she bottomed out. She planted her forelegs further to each side of her and quickened her pace even more, turning the dial on her speed from seven to nine.

“If I didn’t know better, I’d say you’re enjoying this,” Twilight teased, before gently nibbling his other ear. “But I do know better, and I still say you’re enjoying it. You’re limp, you’re thrusting back to meet me, and those moans are moans of pleasure, aren’t they?”

“Mmmphhhhh…” Shining managed, gripping the bed sheets tighter as he blushed, his brow furrowing as he dealt with these strange new sensations building in his body. Twilight continued her pounding, now driving full force and resting all of her weight across her brother’s back.

“This is how it feels when you fuck me,” she purred, tousling his mane. “This is how it feels to be the one not in control. I’m setting the speed and it’s up to you to match it. I can see why the magazine recommends doing this…it feels great!”

And it did feel great. Every time Twilight shoved the thick rubber phallus all the way inside her brother’s firm tailhole, the resounding plap and rebounding force filled her hips and heart with warmth and pleasure.

“So how’s it feel, Shiny? To be fucked by your lil sis?” Twilight placed a hoof on top of her brother’s head and gave his mane a bit of roughening, nearly dislodging the crown from his noggin.“Who’s the Sibling Supreme now?”

“Hhmph…”

“Hey, I know!” Twilight paused to plant a sloppy kiss on her brother’s horn. “I should invite Cadance to do this with you and me sometime. After all, good little fuckboys like you deserve to be used thoroughly~”

Shining didn’t even reply directly anymore; too much of his effort was directed towards breathing heavily through his nostrils. The frequency climbed with each second, and Twilight’s taunts continued in turn:

“Maybe we can make this a new tradition~” An annual pegging. That would definitely spice things up in their relationship.

“Mmph!”

“Maybe we can keep it this way around by default~” A hard sell, but she didn’t expect it to land. It just felt so good to suggest in the moment.

“Hhmmph!”

“Maybe you’ll have to start calling me big sis! That would be so delicious, wouldn’t it, my little Shiny?” The ultimate reversal of power…the little becoming the big, and the tall becoming the small. It felt great on her tongue at least…but she’d love to hear it from Shiny once this was over.

And it was almost over. Twilight could feel Shining’s muscles tightening more and more as he held something big back. His muffled sounds slowly changed:

“Hfff…mmmph…MPH…HHHMPH!”

Shining Armor’s cries quickly climbed in volume and pitch, and before she knew it, Twilight felt something warm and hot shoot onto one of her hind legs…cum. This was it! She’d done it! The crown was hers! And yet, even as Shining came, she could hardly bring herself to slow down at all. She felt like she could do this forever! Why would she have to stop, after all? She didn’t have a refractory period, and the magazine said stallions wouldn’t have one either if they came this way. Maybe they’d go for a second one—

Tap tap tap

“Oh, safe-wording now?” Twilight chuckled as she stopped midthrust and slowly pulled out, feeling the weight of the toy more and more as it slid out of her brother’s hole. As strong as the urge to keep going was, the safeword was sacred, and she’d never ignore it. “Sorry, big bro, got a bit carried away. But that was just…so much fun!” She was a bit winded now from her work, but Shining was wheezing up a storm through his nostrils. Twilight relented some more and undid the straps on his gag, allowing the ball to fall from his mouth. “Wanna try it again sometime?”

“Haah…hah…n-not a…w-well maybe…”

“Shhh, catch your breath there, big bro.” Twilight undid the straps on her strap-on and allowed the fake phallus to fall to the bedsheets, leaving just the smallest hint of a stain from the lubrication still smeared on its surface. With her tool of domination discarded, Twilight moved into aftercare mode, snuggling herself up to Shining’s side. “Are you alright? I didn’t go too hard for you, did I? I was just…kinda trying to mirror what you do to me. Taking control and going in, y’know…”

“I-it…was weird, not gonna lie,” Shining panted. Twilight could see beads of sweat on his forehead, and some trails leading down his neck. “But…after a while I…got an itch deep inside, and you…you scratched it so good that I…”

“Came?” Twilight giggled, and planted a soft kiss on Shining’s lips. “That’s fine. Good, even; I’m glad you enjoyed it! But you do know what that means right?”

“Yeah, yeah…” Shining weakly grabbed the crown from his head and thrust it in Twilight’s direction. “Fair’s fair…”

“Not so fast!” Twilight said, gently pushing his hoof back. “I said if you came, I could take the crown if I so choose.”

Shining blinked, confused. “Which…you do, right?”

“I don’t.” Twilight smiled warmly at Shining, and gently floated the crown back on to his head. “The hard-won helm of the Sibling Supreme is the ultimate treasure, but honestly…giving yourself up to me like that, giving me the opportunity to be the big sister for just a few minutes…that’s Sibling Supreme material. Not just putting on a strap-on and going at it.”

“I am…so confused,” admitted Shining Armor as he sat up, working his jaw around in circles, stretching it after his tangle with the ballgag. “You invite me here to compete for the crown, but then you…let me keep it?”

“You earned it.” Twilight chuckled, looking back towards the discarded strap-on. “I asked Fluttershy for the biggest thing she had in purple and you still took it like a champ. For me. I don’t know what else I could ask a sibling for, other than obvious things like a hug or saving my life.”

Shining smiled in turn, still panting a little as he reached an arm around Twilight’s shoulders and brought her in for a side hug. “Thanks, Twi. You’re the best.” Gears spun briefly in his head as he processed the entirety of what Twilight had said. “Hey, wait, Fluttershy gave you that thing?”

“Oops.” Twilight covered her mouth with a hoof and blushed. “I’m sorry. I shouldn’t have told you that. She has a strict need-to-know basis on her…things. Can you uh, keep a secret?” Twilight finished with a weak, hopeful smile.

“Cross my heart, hope to fly, stick a cupcake in my eye,” promised Shining. “Though I will say I definitely didn’t peg her as the type to have such toys…”

“Yeah, but I pegged you!”

“…okay, true,” Shining acknowledged, rolling his eyes playfully. “But…I have all of today off. What else are we gonna do today? Should I Peggle you up? We gonna play Slides ‘n’ Slithers?”

Twilight’s voice went husky again as her hoof drifted down to Shining’s crotch. “Well…we can do it missionary, just like our first time. I see you’re still plenty hard and need that taken care of…maybe you can do me in the butt too~”

“Today’s full of first times, isn’t it?” Shining asked, laughing as Twilight splayed herself out on the bed again. “First you peg me for the first time, then you give me the crown for the first time, and now I have permission to do the same to you for the first time?”

“Fair’s fair,” replied Twilight, spreading both her legs and wings. “Now come and get me, big bro. I’m all riled up from our time together…”

It was a good thing Twilight had closed all the other doors and windows as well as locking them during her preparations earlier that evening, because the sounds that followed as the two siblings performed act after act of debauchery were quite unusual…but always full of lust and love for each other. And best of all, Twilight had taken her brother down a peg for once, with pegging. That was all that she cared about.

The awesome makeout sessions and sex afterwards were just a bonus.