A Liberal Interpretation of Monogamy

by clopopatra

Rating: mature
Tags: Princess Cadance, Fetish, Shining Armor, Sex, Twilight Sparkle, Anthro, Porn, My Little Pony: Friendship is Magic
Length: 8066

Interdimensional cuckolding awaits as Twilight learns about Flurry Heart's conception.

In the multiverse, there are infinite possibilities. Though one thing is nearly constant: Shining Armor is an infertile beta cuck.

Thankfully, in one universe, a Shining rises above his stature, cuckolding all of his inter-dimensional brothers and ensuring that every Cadance gets at least one good night of loving.

This is the Shining Prime and Twilight Sparkle is about to meet him.

Contains: Cuckolding, Voyeurism, Light BDSM elements, Light Incest elements

Commission for Ploish so many thanks to him for this absolutely fantastic idea. And if you're interested in commissioning me, hit me up on my main.

Cover Art by Sugarlesspaints who is probably one of my favourite horse porn artists out there, so like a billion thank yous to him for letting me use his stuff. Also the piece's derpi code is #2337935. Since uh... apparently that's the way we do it here.

Published 2020-08-31 23:50:00 UTC
Last updated 2020-08-31 23:50:00 UTC

A Liberal Interpretation of Monogamy

“For the nine-hundredth time, no, Twilight,” Princess Cadance said, sounding quite short. Though due to the frequency of Twilight’s questions her tone was incredibly understandable. “While I do appreciate your concern and interest in your niece’s wellbeing. I can not, in good conscience, allow you to poke and prod at her.”

Twilight pursed her lips. “There wouldn’t really be that much poking and prodding involved.”

“And how exactly do you intend to get a blood sample without at least a little bit of poking?” Shining asked, cocking a brow.

Unlike his wife, he seemed far more tolerant of Twilight’s ceaseless interest in the subject. Well… either tolerant or used to it by this point.

Twilight taped a finger against her lip, humming to herself. “I could attempt a teleportation spell to remove a small dosage from her and…”

“No!” Cadance barked, looking away from Twilight and at her husband. “Tell her that she isn’t going to do this.”

Shining shrugged, picking up his mug of coffee and taking a sip. “I mean, I could try. But Twilight, an intellectual mystery, and the word ‘no’ don’t really go well together.” He smirked. “I thought you’d understand that by now.”

Cadance frowned and went silent, poking at her plate of waffles as she tried to parse together some kind of response. When one eventually came, she slowly shook her head and steeled her gaze at Shining. “Then I suggest that your parents should’ve given her a better education when it comes to consent.”

“I mean, sure,” Shining murmured. “But that’s not really something I can go back in time and fix.”

Cadance looked at what remained of her breakfast, decided her appetite had vanished, and shoved it away before looking across the table at Twilight. “And may I ask what about our daughter has gotten you all riled up?”

“I mean…” Twilight took a bite of her eggs, chewing on them and pointing the yolk stained fork at her host, “she’s the first natural born Alicorn to ever exist. She’s a riddle trapped inside of an enigma and I feel like we could push forward our understanding of the metaphysical world by at least a decade with a little bit of tinkering.”

“I’d suggest trying to avoid using the word tinkering, Twily,” Shining teased. “It can kind of put parents on edge.”

“How about investigating?” Twilight asked.

Shining nodded and loudly sipped his drink. “Better.”

Cadance sighed, massaging her temples between her forefinger and thumb. “And what if me and Shining already have a firm understanding on how Flurry Heart was created?”

Twilight’s eyes sparkled, though as she looked at Shining, she saw pure horror on her brother’s face.

“You can’t tell her about… about that,” Shining said. “It’s personal information!”

“Yeah? Well, I’m getting pretty tired of hearing her constantly beg for blood samples and you’re the one who said that she can’t take no for an answer,” Cadance growled.

Shining sighed. “Fair, fair.” He then looked at Twilight, wagging a finger at her. “Though we’re going to need a promise of confidentiality out of you, alright?”

Twilight’s eyes widen. “How confidential are we talking?”

“This is a secret that only me, Cadance, and Sunburst know about,” he said. “And we want as few ears as possible to hear about it. Do you understand?”

“Oh sure, Sunburst can know, but I can’t?” Twilight pouted.

“It’s kind of important that he knows considering he’s our Crystaller,” Cadance explained, taking a sip of her orange juice. “So, if you’re willing to keep what we show you a secret then we might be inclined to share it with you.”

“Does that include…”

Shining nodded. “That includes not being able to publish your findings in a thesis or any scientific publications. This is only for your own personal curiosity and nothing more.”

Twilight bit her lip. She wanted to share her research with the world, for sure, but also not knowing this apparently tippy top secret irked her like none other. She was a Princess and a member of the immediate family, meaning she deserved to at least know the basics of what was going on here.

Right?

Plus, maybe after drafting a compelling thesis, she might be able to show how her research could better Equestrian society. Surely, any such secret would pale in comparison to the good it could bring. All she needed to do was prove that to Cadance and Shining.

So, she nodded. “Alright, I can agree to these terms.”

“Would you swear on your Princesshood?” Cadance asked, lifting a very serious brow.

Twilight held a hand to her chest. “Cross my heart and hope to fly…”

“and stick a cupcake in your eye?” Shining finished, smirking knowingly.

Twilight nodded.

Cadance gave her one final critical glance, as if sizing up the seriousness of her pledge. When no fault could be spotted, she motioned out the kitchen window and at the Crystal Heart outside. “After tonight’s gala, meet us in the plaza.”

The day progressed at a snail’s pace.

The allure of Cadance and Shining’s secret was a constant miasma, nagging at Twilight as she went about the diplomatic affairs of her visit. Documents were bartered and signed, visits were made, and hands shaken.

All of this was done with the secret’s nagging thread tugging at the back of her mind. She wanted to know what these two were hiding but all she could do was try and be patient and endure the day’s formalities.

The clock hadn’t even past eight when Twilight slipped out of the banquet hall, excusing herself with as much discretion as she could afford. She hurried through the corridors in her classy dress, towards the base of the Crystal Palace; to the heart that rested in its bowels.

She stepped into the cool air of the north, shivering as she made her way over to the mythical artifact.

It spun before her in slow rotations, both a soothing and curious presence. It was a mystery to her but one that she forbade herself from ever interfering with. After all, she remembered the last time it had shattered into a million pieces and also remembered a certain childhood story about a sentient egg that required all the Princess’ mares to help put it back together again.

A cautionary tale that showed the futility of such an action of course.

Now where were…

“Well that wasn’t a very obvious exit or anything,” Cadance teased, drawing Twilight’s attention away from the heart and towards her. “Did you want to alert half of my court that something was amiss, or what?”

Both her sister-in-law and brother were dressed in their finest clothes.

Cadance wore a lovely gown made from a blonde silk with emerald and sapphire gemstones for accent. It hugged her impressive figure nicely, with a generous v-cut that showed off her potent bosom.

It was enough to make Twilight blush at her own, far more modest appearance. She had neither the fashion sense or body to compare with her sister-in-law. Though she supposed that this was the advantage of being the Princess of Love.

Meanwhile Shining wore a fine suit designed for such white tie events. He even had a top hat which was tucked away under his arm.

Seeing the two of them standing side-by-side, in such regal clothing, made Twilight oddly aware of their rather strange size difference. Cadance was at least a head taller than her husband, an oddity among most heterosexual couples. Though most heterosexual couples didn’t have an alicorn as one of its members.

Twilight chuckled softly. “Yeah sorry about that. I guess I had uh… something else on my mind is all.”

“And does that something have to do with the Crystal Heart?” Cadance teased.

Her previous irritation had seemed to fade over the course of the day. Though considering the amount of sparkling wine she’d sampled this evening, there might’ve been another factor at play.

Twilight frowned and looked back to it. “I don’t know, does it?”

She could sense Shining come up beside her, and as he stood there, she could feel a certain subtle tension lingering under his façade of coolness.

Was he nervous about this? Nervous about whatever they were going to show her?

Surely, whatever the Crystal Heart had to do with Flurry’s birth couldn’t be that terrible of a revelation. It was powerful and mysterious but it was a power and mystery that was largely under their control.

Twilight held back the question that was lingering on the tip of her tongue, knowing that the answer, if it did arrive, would do so soon enough.

“It’s an impressive little toy, isn’t it?” Shining asked. “Holds the end days at bay, keeps our little oasis alive in the middle of a hostile tundra.” He smirked. “It can do all sorts of fascinating things, really.”

Cadance came up on Twilight’s other side.

“You’re aware of alternative dimensions,” Cadance said. It wasn’t a question but a statement.

Twilight nodded. “Yeah there’s the one that was on the other side of the mirror.”

“Well one of the Crystal Heart’s many functions is that it facilitates the transfer of matter, ideas, and ponies between various other dimensions.” Cadance smirked. “Think of it as that mirror you have but on steroids. Where that mirror can access one dimension, this heart acts as a crossroads between every single dimension where it exists. Hundreds… thousands of Equestrias where the Crystal Heart beats.”

Twilight was taken aback by this revelation, studying the heart with a newfound respect.

“Is that why the mirror was originally here?” Twilight asked.

“Exactly,” Cadance said. “It had been designed and manufactured within the Crystal Empire and Celestia was hoping she could reopen it with the Crystal Heart.”

Twilight looked between them. “And what does that have to do with Flurry Heart?”

Shining chuckled. “Well in our dimension, natural born alicorns can not exist because there is no such thing as a male alicorn. But in other dimensions…”

Twilight snorted, shaking her head. “But that’s silly, you and Cadance made Flurry. You’re her father.”

“Shining Armor is Flurry’s father,” Cadance said, holding onto a tight smile. “Just not this version of him.”

Twilight’s eyes widened. “Does that mean?”

Shining gritted his teeth, a colour creeping into his cheeks.

Cadance held up a hand. “How about we take you on a little tour through the multiverse, Twilight?”

She wasn’t even given a chance to respond before Cadance’s horn glowed, a beam of her mana linking her together with the heart and then covering the three of them in a shroud of magic. Soon the aura covered them completely, blocking the outside world with a dense misty shroud.

It was a teleportation spell of some sort. Twilight recognized the fizzling of ozone from her own attempts with such a spell. Though it was a powerful one, considering it lasted for almost a minute instead of happening instantly. They must’ve been travelling somewhere far away from where they previously stood.

Soon, the aura faded and they inhabited a new realm of utter nothingness.

Twilight looked down at her hooves, seeing that she stood upon some kind of ethereal cobblestone that was made up of ancient magic that glowed as she moved around upon it. It vaguely reminded her of the dream realm but felt far more real than it, having substance and texture.

She looked to her left and then to her right, seeing that both Cadance and Shining were still there with her. They were staring straight ahead at something. And as Twilight followed their gaze, she drew in a sharp breath.

Before them, a lecture hall had materialized. It looked sterile and dull, like any of the ones that could be found on the numerous campuses that littered Equestria. There were several vacant seats, behind empty desks, with a speaker’s podium at the very front. The only thing that was different about this lecture hall was the presence of a comfy looking bed on the stage. A comfy looking bed that was identical to the one in the royal bedchambers.

A bell rang, the noise muffled and dull, sounding like it was coming out of a fishbowl and trying to enter another.

“The Crystal Heart acts as a terminus between millions of realities, where hundreds of thousands of Cadances and Shining Armors rule over the Crystal Empire,” Cadance explained. “Most of whom are cursed with a similar affliction.”

As Twilight glanced at Shining, she saw that her brother was blushing, his gaze flinching away from her as if he were humiliated.

“And what affliction is that?” Twilight asked.

Suddenly a door to the lecture hall opened and in came today’s class.

A dozen Shining Armors and a dozen Cadances stepped into the room. They all looked essentially the same with only minor differences between them. One Shining had a beard, one Cadance had a scar on her cheek, one Shining wore a stallionbun, and another Cadance needed glasses.

They all filed into the room and took their seats, chatting amongst themselves like any class would before a lecture. Twilight had been to enough campuses to know this song and dance well, even if the class was a bit eerie to witness.

Cadance, the one beside her, sighed. “We’re all linked together by the fact that in our home universes we have failed to procreate.”

Twilight blushed. “Pardon?”

“I’m essentially infertile, Twilight,” Shining whispered. “Well that’s not true but…”

“Mortal sperm is not meant to penetrate an alicorn’s eggs,” Cadance explained.

“But… but…” Twilight shook her head, unwilling to believe this. “You have a daughter, you couldn’t possibly…”

Cadance snorted, drawing Twilight’s attention towards her. “If there are millions of universes with just as many possibilities, then it only makes mathematical sense that there are certain rare universes where Shining isn’t plagued by this affliction.” She glanced at her husband, offering the warmest smile she could muster. “And you know that I don’t think any less of you for this, right?”

“I know dear,” Shining said, offering his own unsure smile in return. “It just means that we had to get a bit more creative about finding a solution.”

“And what’s that solution?” Twilight asked.

Before she was even aware of it, she was within that lecture hall, seated at one of the many desks, somewhere near the back. She did a quick check, confirming that her brother and sister-in-law were still beside her.

She gulped. “I feel a little…”

Cadance shook her head. “Don’t worry about it. You aren’t the first Twilight who’s ever been here before. Sometimes one us brings a guest to witness these lectures and believe it or not you have a ceaseless intellect in more than just one reality.”

“A terrifying revelation,” Shining teased.

One of the other Shining’s looked over at them and chuckled. “Oh hey 156, your Twily is still alive?”

Shining nodded. “Yeah, 295.”

Twilight deadpanned.

Well that was a horrifying little discovery to make.

A few more Shinings and Cadances turned to greet her, treating her as just another lecture mate.

“So, who’s the teacher then?” Twilight asked.

Before anyone could answer, the door opened and their professor entered.

It was Shining, though a version that Twilight struggled to really comprehend. He was taller than her actual brother, towering over even the alicorn princesses in attendance. Though this wasn’t too surprising, considering that he was also an alicorn.

He was strong, muscular, powerful, his white shirt unbuttoned to show off rows of abs as if he were the hero in a dime novel romance. And his hair was flowing, gorgeous and long. He looked like a version of Shining Armor who could win a dozen Sibling Supreme Contests in a row and still have enough left in the tank to rule over his kingdom as if it were some kind of mere side gig to keep himself busy.

This Shining moved towards the desk, placing down a briefcase upon it.

“Hello everypony,” he said.

Gods… even his voice sounded stronger, coming out as a booming baritone.

“Hey Number One,” the students all chanted in unison.

Twilight’s Cadance whispered. “This is Shining Prime, or Shining One. He’s from the ‘correct’ version of Equestria where he ascended alongside me.”

That phrase sent a chill down Twilight’s spine. Who got to say which Equestria was considered ‘correct’?

“It looks like we have a guest today,” Shining Prime said, motioning to Twilight.

She grinned sheepishly in response. “Sorry, I uh… I bugged Shining and Cadance to let me watch. Is that… alright?””

“And have they ruined our surprise?” Shining Prime asked.

Shining, her actual brother, shook his head. “Not yet.”

“Very good.” Shining Prime stepped away from the desk and looked out upon the room. “Sorry to be a bit unprofessional but I’m terrible with faces.” He smirked. “Especially when half of them are my own. Can we have a quick show of hands from the Cadances who have not had their Flurry Hearts or Florenzos, yet?”

Florenzo?

“Sometimes I give birth to a son,” Cadance explained.

Twilight watched as a few Cadances, who looked a little younger, all lifted their hands.

Shining Prime studied them closely, humming and hawing to himself as he had his pick of the litter. Finally, he pointed to one who was seated a row down and a few seats over from Twilight. This was the one who had a small scar on her cheek.

“Do you want to be today’s volunteer?” he asked.

She apparently didn’t need to be asked twice as she eagerly bounced to her hooves and moved towards the stage.

“And what’s your name?” Shining Prime asked.

This Cadance looked towards the class with a huge smile. “Cadance Number 307.”

“Well 307, are you ready to be a mother?”

This Cadance nodded quickly, making her way over to the bed and sitting down upon it.

Then it dawned on Twilight what that bed was meant for. And just like that, her expression shifted from intrigued to downright horrified.

Were these two going to…

Shining Prime seemed to be reading her mind as he looked directly at her and shot off a coy grin. “Sorry, Twily, but this is going to get pretty awkward for you.”

He gripped his shirt and ripped it off in one smooth motion as he moved towards the bed, showing off his barreling torso.

He threw caution to the wind as he grabbed this Cadance, pulling her back to her hooves and into a passionate kiss. Their mouths melded together hungerly and his hand shot under the hem of her skirt, with equal appetite, ensuring both sets of lips were given the attention they deserved.

Twilight looked around the room, seeing the Cadances watching with unrestrained glee and perversion. Some of them were even bold enough to start playing with themselves, as if getting off to the display. After all, how often did you get to enjoy live pornography of yourself.

The Shinings also didn’t seem to mind. Some awkwardly shifted back and forth in their seats. Others stroked themselves, regrettably giving Twilight the first look of her brother’s dick that she’d ever had. And yet others started to fool around with their respective Cadances, making out or doing some very heavy petting.

For Twilight, her Cadance was biting her lip and watching intently, while her Shining shifted awkwardly in his chair, a bulge present in his pants.

Twilight swallowed a lump in her throat. “Wait… does this mean that you’re getting cucked by…”

“By myself?” Shining asked, his cheeks warming just a little bit further. “Essentially yes. But the pill is a lot easier to swallow when you realize that ninety-nine percent of all the Shinings in the multiverse are getting cucked by one of the Shining Primes.”

“There’s more than one?” Twilight asked.

Cadance nodded. “Look around the room.”

She did, trying to figure out what she was supposed to see. Then she noticed it, a slight glow that seemed to form around all of the Shining Armors in the room, a faint yellow that clung to them like some kind of ethereal shroud.

“By watching Shining Prime in the act,” Cadance explained. “A part of his essence gets imbued into them. Meaning that one day, with enough cuckolding, they may become Shining Primes themselves. Ready to serve the never-ending number of Cadances in the multiverse.”

Shining made a little moaning sound, bringing Twilight’s attention back to the stage.

The Shining Prime had seated his Cadance back upon the bed, grabbing her blouse and tearing it open like a brute, sending buttons flying outwards in every direction. Though this Cadance apparently enjoyed the roughness, letting out a pleasured little whinny as he trailed kisses down from her cheek, along her neck, and across her heavy breasts.

He licked his lips before taking one of her nipples between them, suckling upon it roughly.

At the same time, he maintained a hand under her skirt, his digits pumping into something which the thin fabric obscured from Twilight’s view.

“Remember when he defiled me?” Twilight’s Cadance asked.

Her Shining nodded. “I had no idea you were into so many kinks, dear.”

“Neither did I.” She sighed fondly. “A shame that his seed caught on the first attempt.”

“It always does,” Shining murmured.

Shining Prime drew back slowly, leering at his Cadance as he stood up nice and tall. He still wore pants, though an impressive bulge, far larger than a regular Shinings, was nestled within them.

“Disrobe,” he instructed.

And the Cadance obeyed without question, shedding her tattered blouse and yanking off her skirt with a little wiggling of her hips. This is when Twilight learned just how beautiful her sister-in-law really was.

Not that Twilight was jealous or anything, of course not.

“On your knees,” Shining Prime ordered, making a show of stepping around her and appraising her.

The Cadance obeyed, falling to her knees and looking up at Shining Prime with nothing but pure adoration in her gaze.

Twilight’s face burned bright red as Shining Prime reached for his belt, pulling it off slowly. She heard the heavy leather clap against each of the loops in his pants, even from this distance away. It retreated at a snail’s pace, drawing out these tense moments, and when it was finally freed, he folded it once, creating a very dangerous switch.

Shining Prime hummed to himself and looked towards his audience, his pupils. “Does anypony want to see a little BDSM tonight?”

All of the Cadances, including the one next to Twilight, nodded along eagerly. Meanwhile all of the Shinings seemed a bit more hesitant. Likely they had never really entertained the idea of doing this kind of thing with their wives. Though Twilight supposed that was another deficit that the multiverse had implanted upon them, a kindness that not even roleplay or Cadance’s desires could cure.

Shining Prime grinned and held the belt against the bottom of Cadance’s muzzle, turning her gaze up to meet his own. “And would you be interested in letting me colour your ass before I breed you?”

This Cadance grinned such a dopey grin. Twilight almost wanted to use the word bimbo-ish to describe it but held back, realizing that this was still a version of her sister-in-law and it would be most impolite to call her such.

“Of course, Master,” Cadance said, her voice flittering forth with all sorts of lewd and sinister intentions.

Shining Prime smirked and reached forward with his hand, gently running it through her hair. He whispered something to her, his voice low enough that Twilight couldn’t pick up on what he said. Though clearly this Cadance had, as she nodded along, giving her consent to whatever, he had requested.

Suddenly, he grabbed a fistful of her hair and yanked upon it sharply, jerking her head to the side. The Cadance gasped, whimpering as he forced her to change positions and return to the bed, crawling upon her hands and knees.

The various Cadances sat on the edge of their seats and Twilight winced. Though as she studied the room, no one else seemed very plussed by the whole display.

Clearly this was not out of the ordinary.

“Sorry that you had to find out this way,” Cadance whispered.

Twilight looked over at her sister-in-law, blushing as she noticed that she’d hiked up her regal dress and was pumping her fingers swiftly into her hungry little snatch. Cadance moaned softly as she glanced at Twilight, winking at her playfully.

Why had her sister-in-law forgone panties this evening? Surely, that was most…

“Find out what?” Twilight asked, rubbing her thighs together and burning with shame. Had she really gotten wet watching the alternative dimension version of her family going at it. Was she really some kind of incestual voyeur?

Cadance grunted, gasping as she found much success in her masturbation, “That… that I might have a thing for tough men who treat me poorly.”

“Do you and Shining do this kind of…”

Cadance shook her head, snorting. “No but we tried after attending a few of these lectures. Shining is a dear but he hasn’t gone to enough of these to get that sadistic little fury.” She glanced at her husband and sighed. “Soon enough though…”

Twilight looked at her brother.

He nodded though his jaw seemed tense and expression rather hard to read. Of all the Shinings here, he seemed to be taking it the best. A few of his clones were reserved like him, a few more were teary-eyed and upset, and one Shining, whose Cadance was on stage, had a few humiliated tears drawing darkened streaks across his cheeks.

Why were so many universes so cruel to her brother?

A gasp tore Twilight’s attention away from the students and back towards the stage.

At this point, Shining Prime had Cadance bent over the edge of her bed, her rump facing the room and hiked high into the air. Twilight could see her pussy and the way that her arousal coated it so utterly, dripping along her quivering thighs.

Shining Prime sat beside her, pinning her head against the sheets with one hand as he used the other to slowly circle her large butt with the belt. He was warming her up and preparing her for the brutally he clearly had in mind.

“I think we’ll start with twenty lashes to warm you up,” he said, loud enough that it was obvious that this was part of the performance.

He then drew the belt back, leveling it a good couple of inches away from Cadance’s plush rump. A second passed, a moment to allow the tension to fester. Then he lashed out, slamming the material across her cheek with a potent crack.

It sounded like a gunshot, snapping loudly across her plush flesh. The only sound more potent than the actual impact was the tortured little yelp that jerked free from Cadance’s parted lips.

The Cadance quivered and quaked, squirming feebly though Shining Prime kept her easily restrained with a firm hand on the back of her head.

Of course, a nice red lash lingered behind upon Cadance’s rump. It was soon joined by a second and third, each coming down with the same amount of intensity and brutal strength.

Yet, no matter how hard Shining Prime struck her, this Cadance’s moans refused to abate, her pleasure failing to wane. If anything, the moisture that clung to her thighs only grew more intense, rolling down her quivering legs in thick sheets.

Shining Prime drew his arm back, further than any of his previous blows, holding the belt high above his partner’s already coloured ass. The hand, on the back of her head, slackened and he instead started stroking her hair tenderly. A few more hushed words were spoken and Twilight noticed the nod she gave.

And then, he slammed his belt down, cracking it roughly across Cadance’s ass and using an impressive fraction of his powerful strength. Cadance yelped with legitimate pain and a truly impressive mark was left behind. One which would surely bruise and linger, bothering this Cadance for the many days ahead.

“Good girl,” Shining Prime cooed, taking a moment to both stroke her hair, with his hand, and her butt, using the coarse tip of the belt. He then looked to his audience. “How many of you have the courage to do something like this to your wife?”

All of the Shinings looked away, refusing to meet his gaze. This seemed to please him as he snorted, his eyes now settling on Twilight.

“How about you?” he asked. “Does this Twily have a thing for getting her ass beaten?” He then grinned nice and wide. “Or maybe for beating other ponies’ asses?”

Twilight’s face burned even brighter than Cadance’s rump as she felt the lecture hall’s eyes fall upon her. She swallowed a lump in her throat and cracked a nervous smile. “No comment?”

Shining Prime chuckled and then nodded to the Cadance beside Twilight. “And how have you been, babe?”

Cadance smirked. “Well…” She drew her fingers out from under her dress, holding up two digits that were coated in slick fluids. “I guess I was a little needier than I realized, Shinny.”

“Then maybe I could see about fitting you in for a little one-on-one tutorial after I’m done here,” he said, flashing a grin.

Twilight’s Shining tensed.

“Oh, I wouldn’t know about that,” Cadance said, batting her eyelashes. “As much as I’d love to double dip, I don’t think it’d be especially fair to all the other Cadances who haven’t had a shot with you yet.” She snorted. “Plus, one child is plenty, in my opinion.”

Twilight noticed that a few other Cadances nodded along to this, obviously being part of that cast who hadn’t had a chance to play yet and were desperately looking forward to it.

Shining Prime merely nodded, turning his attention back to his current Cadance. He cooed softly, moving the hand away from her hair and along her back, tracing a pair of powerful digits along her spine.

“You’re soaking,” he teased, placing the belt against her other flank. “Do you want to be bred?”

Cadance nodded eagerly, whining as words failed her.

Shining Prime smirked. “How about a few more lashes, just to make the colour even?”

His fingers went between her legs, two of them stroking away at her soaking wet lower lips. He parted them slowly, pressing into her without too much fuss. Two digits seemed to be enough to sate her, causing a pleasured chirp to come forth and her hips to grind against the sheets instinctively.

He slowly pumped them into her, drawing the belt away. He delivered a blow, the leather clapping firmly against her bottom.

A strange noise jerked forth from her lips. It was one-part moan and another pained grunt. The two noises fused together seamlessly, melding into something that was more erotic than either alone.

His fingers continued to stroke and play with Cadance, a third slipping into her folds as he hammered away without restraint. Yet again, he clapped the leather against her rump, again and again. Each potent lash drew forth a faithful replica of that noise, her melody rising in tune with the constant clap of the belt.

Cadance’s voice remained strong, both pleasured and tortured all in one. Soon her entire rump was alight with streaks of red colouring it abundantly.

The final blow was another mighty lash. It impacted with such fury, jerking free another legitimately pained howl, which lingered on the air with such energy.

Shining Prime waited for his Cadance’s agony to abate before tossing the belt aside. Now that this other hand was free, he used it to stroke at Cadance’s clit, treating it roughly as the fingers inside of her continued to rapidly pound away.

Soon Cadance’s screams were replaced by moans that filled the room, reverberating off of the lecture hall’s stucco walls.

Twilight felt her cheeks warm and a small fire smolder within her gullet. She was tempted to join Cadance and start touching herself but knew how weird the sight would be. Could she really look either of them in the eye if she started to get off to this?

Twilight’s Cadance snorted. “Just do it Twilight. Pretty much every other version of you has at some point.”

“Is it that obvious?” Twilight asked.

“I can feel how horny you are, dear. Lust is just a lesser form of love and that’s my special talent after all.”

Twilight mulled it over, hoping some last bastion of common sense and sound judgement would talk her down. But when none did, she said fuck it and hiked up them hem of her dress, exposing her soaking wet panties.

She drew them down unceremoniously and promptly crammed two fingers into her needy little cunt, throwing caution and common decency to the wind.

Almost instantly that fire in her gullet was tamed, controlled, and used for its intended purpose. And soon, her posture stiffened and cheeks warmed as a faint moan came flittering forth from her lips.

Her Cadance grinned. “What happens in the ether stays in the ether, right?”

Twilight nodded quickly, too busy sating her lust to really offer up any other form of proper rebuttal.

Fuck, it felt so good to just let loose and enjoy herself.

She threw her brother a sheepish grin, though he didn’t seem to catch it, forcing his gaze towards the stage.

It was an awkward evening, to say the least, but hey sometimes families just… you know…

Okay! There was literally no way to spin this that didn’t just make it sound even worse.

Shining Prime, meanwhile, was getting his Cadance right to the edge of orgasm. It was obvious, watching her shudder and quake with such unrestrained glee. Her voice had not waned, staying nice and level, coming out in frantic little puffs of exertion. She was panting and crying out Shining’s name, begging him to go even harder.

“Now the key to ensuring that the pregnancy catches,” Shining Prime lectured, grunting along with his fingering. “Is to ensure that your Cadance has several orgasms over the course of your session.” He then smirked darkly. “Not that I really expect any of you to know how to do that.”

Twilight’s Shining huffed, murmuring under his breath. “I’ve gotten two from Cadance before.”

Before Twilight’s Cadance could weigh in, the Cadance on the bed seized and let out a final gasp. Her whole body shivered as she soon climaxed.

Twilight was amazed, watching the gush of fluids come rocketing forth. Not even Shining’s digits managed to really stem the flow as a solid geyser of arousal came gushing forth and exploded outwards. These juices didn’t just leak onto the bed but gushed onto the floor, and a few potent droplets managed to fly off stage.

Shining Prime drew his digits out, bringing the fluid drenched ones to his mouth and tasting them. As he did so, he used his clean hand to gently pat Cadance’s reddened bottom.

He moaned at the flavour, taking a greedy second sample before wiping them clean on his pants.

“Delectable as always Cadance,” he said, standing up.

His horn then glowed and he turned the bed ninety degrees, making it so the audience had a sideways profile of Cadance and himself. He then stepped around to her rear, using a second burst of magic to raise the bed, bringing both of their hips in line.

Finally, he reached down and unzipped his fly, rocking his hips back and forth and wiggling out of his tight fitted pants. What sprung forth didn’t seem possible, the impressive cock was both thicker and longer than any Twilight had ever seen, even in the abundant porn she consumed.

Yet, there it was, real and pulsing with a latent masculine energy.

Shining Prime, touching a pair of fingers to it, traced them down from the unflared head, past the bulging medial ring, and finally rested them against the base. It was a tantalizing journey that Twilight couldn’t help but gawk at.

The Cadances seemed to just eat this up, all of them leaning forwards in their seats. A few Shinings also seemed impressed by it, though most were either embarrassed by the sight or kept a stiff upper lip and attempted to hide their emotions behind a mask of poorly restrained humiliation.

Twilight was enthralled by the sight, feeling herself get turned on by it. Though this attitude also came with a nice ration of shame and humiliation, realizing that she was essentially getting turned on by her own brother’s cock.

Just… an alternative dimension version of himself.

In that case was it even really incest?

…

Best not to justify it, Sparkle!

Shining Prime rested his fat cock between Cadance’s flanks, idly rocking it back and forth.

Twilight doubted that such an organ could fit inside of her, yet, he seemed set to prove her wrong.

After a few moments of rocking back and forth, he drew back, lining up the tip with Cadance’s swollen lower lips. When it was probing at them, he inched forwards, parting her cunt and pressing deep into her.

Cadance’s back arched and she moaned loudly, her hips eagerly rocking back against him, though he denied her any further penetration.

“You know what I love about fucking your wives?” Shining Prime asked, looking to his cuckolded inferiors. “I love how tight they get; how desperate they are for a real cock.” He chuckled and grabbed Cadance’s hips roughly. “All they want is a good dicking. Just perfect little cock socks all around. What’s not to love about them, right?”

With his new leverage, he began to pump into Cadance, his initial progress halting and slow. He may have acted like a brute but when it came to the actual act of fornication, he was a lot more elegant with his treatment.

Twilight could feel her heart flutter and wrist ache, her digits slick with arousal. As she glanced at Cadance, she saw that her sister-in-law was in a similar state, likely recalling all of the depraved things this Shining Prime had done to her.

There was a fire within Twilight’s core, one which was contained but still smoldering, begging her to snuff out the flames with an orgasm. She could, if she were willing, provide it with this sacrifice and tribute. Though was she really willing to indulge in this with Shining beside her? With a dozen clones of her brother all present for such a degrading act of perversion?

She watched as Shining Prime’s pace picked up, his tempo reigniting as he started to pump into her more and more swiftly. One of his hands slid away from her side and he instead grabbed her tail, coiling it around his palm and yanking back on it for leverage.

And as Twilight watched this Cadance get bred like a whore, she imagined herself receiving a similar treatment, a similar bout of depravity that was so tempting and delicious. That’s when she realized that no matter what she did, she would crave this cock no matter who it was attached to. And with that depraved nucellus at the centre of her thoughts, she knew she could allow herself this most blissful of sensations, this most pleasurable of surrenders.

Her own posture tensed, along with the Cadance on stage.

By now, Shining Prime was railing her roughly, his impressively sized cock somehow fitting inside of her with no problem. It was like her cunt was a specially designed sleeve to ensure Shining Prime’s pleasure. Though considering the nature of fate, reality, and apparently, the Crystal Heart, Twilight had no doubt that nature had been influenced to make this concession.

The breeding grew more and more animalistic. One hand was clenched tightly around Cadance’s tail and the other was pressing her roughly into the sheets. Shining Prime’s tempo was sporadic, forceful, and swift, their hips clapping together roughly, the wet noises loud enough that Twilight could hear it from the back row. It was loud enough to cover the sound of slurps and belches coming from her own unrelenting fingering.

The Cadance on stage moaned without restraint, her fingers digging into the sheets as Shining Prime demolished her. There’d be no way she’d be sitting down comfortable this week after getting a rutting like this.

Shining Prime grunted and groaned, his powerful core shuddering as he very obviously tried to deny himself his own orgasm. He was likely waiting for Cadance to have her own first, making sure that this breeding actually took.

Not that he was left waiting for long. It took maybe another half a dozen potent and vicious thrusts before Cadance cried out his name. Her whole body went rigid as if a current was going through it. And as her walls clenched around his shaft, he delivered one last feeble thrust. The meekness of it was more shocking than the finality.

There, hilted inside of her, he came, hard.

Twilight watched in awe as he pumped her full of his seed, the leftovers gushing out upon the bed. She’d never seen so much cum before, thinking that such an abundant dosage was more a product of myths and legends. Surely this was not something that actual mortals could produce.

Yet, here they were with a ration that should’ve been impossible. Though Twilight quickly realized that this Shining was special, avoiding the humble limitations of mortality by being an alicorn.

And as their orgasm started to abate, Twilight’s came along for the ride. She used her other hand to muffle her voice as she felt her juices gush around her fingers, spilling forth eagerly. She tried her best to contain them but blushed as she realized that this was fruitless as they overwhelmed her, staining the back of her dress and the seat she occupied.

She looked around and most of the eyes were upon the stage. All of them except for her own Cadance, who glanced at her, winked, and offered a knowing smile. She said nothing though, simply removing her own fluid-soaked digits from under the hem of her pricy gown and wiping them off on the desk.

Shining Prime drew out of Cadance, who gasped as his still impressive organ popped out. It had flared, the head growing even thicker than before. And as it slowly departed, a belch of potent fluids followed, further fouling the bedding that they had fucked upon.

He looked around the room. “And that, gentleman, is how you breed a mare.” He then nodded to the only Shining who was alone, cocking a finger gun at him. “No need to thank me, dude, but you should be expecting ‘your’ daughter in about nine-to-twelve months, depending on how biology works in your dimension.”

Finally, he sighed and wiped his brow. Clearly the ambitious bout of fucking had taken quite a bit out of him.

Though before he dismissed anypony, he looked towards Twilight, smirking. “Well I hope that answers all your questions.”

Twilight flushed, realizing how frayed her own appearance must’ve been. “Yes, that was…” she cleared her throat, feeling red creep into her cheeks, “that was quite informative. Thank you for letting me sit in for one of your lectures.”

“It’s always exciting to see a fresh face,” Shining Prime said before shaking his head. “Well… fresh compared to seeing a dozen of me and a dozen of my wife at least.”

With that concluded, he marched towards the podium, not even bothering to put his clothes back on.

“Well I think that about concludes today’s tutorial,” he said. “Remember, you don’t need to be me to give your wife a good time. Just don’t be afraid to get a little rough every now and then and also ensure that you provide her with plenty of earth-shattering orgasms.” He cleared his throat and made a show of looking at his wrist, as if there was a watch there - which there wasn’t. “And class is… dismissed!”

A few Shining got up and made their way towards the exit, looking relatively cool and collected. A few more were in a bit rougher shape, their egos clearly bruised and their eyes tearing up just a little, looking quite misty. These Shinings were consoled by their Cadances, who were likely telling them that they would be like that someday and that it wasn’t so bad.

One Shining looked utterly defeated, though, his gaze downcast and ears drooping. This was the Shining who was alone, his wife currently laid out upon the bed, another stallion’s cum belching from her loins. Twilight didn’t envy his position in the slightest.

Twilight looked at her own Shining. He seemed to be troubled but at the very least he wasn’t devastated by the display. If anything, he was probably more perplexed by the fact that his sister had just jilled off beside him, while watching what was essentially him fucking his wife.

Admittedly, that was pretty fucking awkward.

“Are all the Shining’s like that?” Twilight asked, whispering as she motioned to the broken-hearted Shining in front of them.

Cadance pursed her lips and nodded slowly. “They all get like that at first and it’s especially rough when you’re the one whose wife is getting bred.” Cadance shuddered as a memory struck her. “Though to be fair it’s the price you pay to take these lessons and one day become like him.” She looked at her husband and sighed. “I remember that you looked so adorable when it was finally my turn to get bred. It just broke your little heart into a million tiny pieces.”

“Yes,” Shining murmured, flinching away from that very same memory. “It was quite traumatic.”

“At least we got a daughter out of it,” Cadance commented, smoothing out her dress and standing up. “Come on, we better get out of here.”

Twilight looked at the one last remaining Shining, his jaw gaping as Shining Prime returned to the bed, cuddling with his wife.

“Yeah that’s a good idea,” she said.

Cadance’s horn glowed and instead of taking the traditional exit, they faded back into the ethereal realm.

“Well that was very insightful,” Twilight mumbled, more than a little shellshocked at what she’d just seen.

Shining nodded. “And can you see why we were more than a little hesitant about divulging this kind of information?”

Twilight was silent for a moment and Cadance took this as a chance to remove them from the ethereal realm, fading them back into their reality, right outside of the Crystal Heart.

It would seem that no time had really passed. It was the same cold evening and the moon hadn’t moved in the night sky. If you weren’t privy to this most sensitive of information, you wouldn’t have known that a half an hour lecture on cuckolding had just taken place.

“So, that’s the story,” Cadance said, continuing to smooth out her frayed appearance now that they were back in public. Clearly, she’d need to change before returning to the gala.

Twilight nodded, feeling her mind abuzz with questions.

And when that happened, she couldn’t help but let them come spewing forth.

“How many different versions of you are there?” she asked Cadance.

“How many times have you been cucked by yourself since you discovered the heart?” This question to Shining.

“How do you know when these types of lectures are going to take place?” Now to both of them, giving neither a chance to respond,

Twilight drew in a breath. “How do you-”

Shining’s complexion burned bright red and he held a finger to his lips, shushing Twilight. All the while, Cadance snickered behind her hand.

Twilight was confused by such a reaction until she noticed that there were a few guards patrolling the area, prime witnesses who could overhear them.

So, she sheepishly grinned instead. “Maybe we could take this somewhere private?”

Cadance glanced at Shining whose complexion was such a beautiful shade of pink.

“I think that’s a good idea,” she said. “The last thing I need is for my husband to die of embarrassment before he becomes a Prime.”

Author's Note

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