Bonds and Boundaries

by Dusk Raven

Rating: mature
Tags: Shining Armor, Twilight Sparkle, Drama, My Little Pony: Friendship is Magic, Fetish, Romance, Porn, Sex
Length: 7350

Shining Armor and Twilight Sparkle are as close as siblings can be. But Twilight can imagine being even closer.

Twilight Sparkle and Shining Armor are more than just siblings - they're best friends, with an unbreakable bond and an intimate understanding. But when a minor slip leads to some personal physical contact, Twilight realizes there's something missing - something they haven't shared.

Unable to imagine anypony meaning more to her than her brother, she comes to him with a proposal - one that will make them both think hard about what they want their relationship to be.

Written for the Incest is Wincest April 2019 contest.

This'll be a bit of a slow burn - I believe good porn requires good context. For those who want to skip right to it, however, Chapter 3 is the one you're looking for.

Cover pic is a cropped version of a pic by Crash/Crash9902. You may find it on Derpibooru under the latter name.

Published 2019-04-30 06:00:01 UTC
Last updated 2019-04-30 06:00:01 UTC

1: Play

“Hi, Shiny!”

“Hey, Twily.”

As usual, Twilight’s energetic greeting was met with Shining’s more measured, but still cheerful reply. It was something of a ritual for them, whenever the two met after returning home - Twilight from his her classes, and Shining from his Royal Guard training. While they exchanged greetings, Twilight trotted up to her brother and nuzzled his neck and chest – those being the only parts of him she could really reach. Meanwhile, Shining wrapped a forehoof around her, pulling her close and tucking her head under his, careful not to poke himself on her horn. This too, was part of their reunion ritual – though they held the embrace for longer than one would expect of two siblings.

But then again, it was beyond most ponies’ expectations for a physically-powerful young stallion in training to be a Royal Guard to be so close to an intellectually and magically brilliant young mare – even if they were brother and sister.

“You’re home early,” Twilight said, giving him a kiss on the cheek.

“Yeah, today was kind of a short day for training, and a lot of it was just going over protocol and etiquette. So… I’m home early.” He smiled. “Good thing too, because mom and dad are going to be out until later tonight.”

“I see. Where’s Spike?” She looked around, as if expecting him to appear from behind a lamppost or something.

“He’s taking a nap right now. I played some games with him when I got home, and that probably tired him out.” Finally, Shining Armor broke the hug, removing his hoof from her and taking a single hoofstep back.

Twilight giggled. “Either that or he just wanted to get some sleep in before I got home. So, just the two of us, then?” Twilight looked up at him as she smiled.

Shining grinned. “Don’t worry, I’m pretty sure I can handle you by myself.”

“Hey, I’m not a filly anymore, I don’t need a foal-sitter.” She grinned. “Although I wouldn’t mind if you invited Cadance over.”

Shining shook his head.“ Not on such short notice, I’m afraid. She’s been pretty busy lately… speaking of which, how was your day?”

“Yep!” Twilight beamed. “Today we went over new alchemical techniques, studied some primary sources from the time of the Battle of Hollow Shades, and had a test on the proper balancing of magical formulae in spells! Specifically, those dealing with the Inari, Exort, and Wex energies!”

Shining Armor chuckled. “Do I even need to ask how you did?”

Twilight giggled. “Am I that predictable?”

Shining chuckled. “At acing tests, yes.”

“Well, I dunno about that...” She frowned slightly. “Some of the formulae were tricky. Exort’s effects increase exponentially rather than linearly, and Wex tends to react weirdly with certain magical matrices. I hope I passed...”

“I’m sure you did!” Shining Armor shook his head, smiling. Twilight seemed to worry too much about passing tests to the point that she didn’t realize she generally aced them… unless, of course, acing and passing were the same thing to her. Either way, she had a huge fear of failure… so it was up to Shining to make sure she didn’t obsess over it. “Well, it’s a good thing it’s challenging, right? Makes you really use that brain of yours.” He reached out with a hoof and patted her head. “Otherwise, you’d probably fall asleep during the test.”

Twilight let out a mock gasp. “Fall asleep? In class?! Never!” She giggled again. “But you’re probably right. The harder stuff makes me feel like I’m learning more.”

Shining nodded. “Winning’s always more satisfying when you really have to work for it. You also can’t improve unless you’re being challenged.”

Twilight nodded. “Sounds reasonable to me!” She grinned. “Hey, do you want to help me study?”

“Sure!” Shining said. “Do you want Spike to help, too?”

Twilight shook her head. “Nah, let him have his rest. I’ll do just fine with you.” She smiled before trotting off to the house’s study.

Truth be told, most of Twilight’s study material went over Shining’s head. Despite his looks and life goals, he wasn’t a stranger to intellectual matters – his fellow Ogres and Oubliettes players from back in high school could attest to that – but Twilight was a genius, and anything that could challenge her was several levels higher than anything he was ever taught, even in college. And she was still young enough to be going to high-school!

But oddly, Shining didn’t feel too bad about that – he actually liked helping her study. Sometimes he could help in unexpected ways – Twilight was still rather linear in her thought process, and sometimes he could spot simple solutions or approaches that were staring at her in the face, while she was too fixated on something else to notice. The rest of the time, of course, it was a pleasure to watch her work, to listen to her solve problems out loud, to study subjects that would baffle ponies much older than her. Rather than feeling outclassed, he felt proud of her.

But more than all that, he just liked being with her.

The pair were soon in their house’s study room, where a sizable desk served as Twilight’s work area. Behind it on the wall was a corkboard, still holding notes from Twilight’s previous study session. Around it were shelves of reference books and whatever textbooks Twilight hadn’t placed in her backpack for the day. Spare writing materials were never out of sight at the edges of the desk. And, of course, to the side was a large comfy chair for Shining to sit in while his sister worked. It was important to settle in and get comfortable, because Twilight could spend a long time studying.

Unfortunately, there wasn’t much for Shining to help with. Most of what Twilight was studying involved magical formulae – reviewing the material that had challenged her on the test. While Shining had new something of certain spell matrices and the energies that powered them, the fact was that most unicorns used magic out of instinct, generally relating to their cutie marks, and likely had no idea how their spells really worked – at least, not to the technical detail that Twilight did. Shining Armor’s knowledge was limited to how to modulate barrier spells, to alter their shape, size, or add special features like what Twilight called selective tangibility – a fancy way of saying that a shield could be solid to some objects but as far as others were concerned, not even there.

He’d discussed all that with Twilight long ago… so, naturally, she had shield spells down pat, and everything she needed help with involved things Shining didn’t have a Cutie Mark in.

Normally, at this point in the day he’d be worn out from training and content to sit and watch Twilight work. But today had been an easy day, and he had a lot of energy just waiting to be used. He was also getting bored – a dangerous combination.

“All right, that should do it,” Twilight said proudly, setting her quill aside and levitating up the paper on which she had designed – and solved – a particularly challenging formula. “That sure was a tough one, but after taking that on, I think I…” Her voice trailed off as she spun her chair to face Shining, only to find that his chair was vacant. Her first thought, of course, was that he’d left to use the bathroom or get a snack without telling her, and that he’d be back. But, she really wanted a certain somepony to appreciate the work she’d done, so she quickly trotted out of the study in search of him, paper levitating behind.

Sometimes, Shining surprised her by coming up with ideas she hadn’t thought of. This time, he surprised her by leaping up from behind the couch and pouncing on her as she passed by. She was completely bowled over, landing on her side on the soft carpet. As she squealed in surprise, Shining placed a hoof on her, gently holding her down. “Gotcha.”

“What in the world was that for?” Twilight scowled, though her tone was playful, and she struggled against the hoof holding her down. Both of them were well aware that she could easily fling him off her with her magic - but where was the fun in that?

“You need to be more vigilant, Twiley.” Shining tsked at her. “You never know when you might be ambushed! Now, what would you do if somepony pinned you down like this?”

“Maybe something like… this!” She suddenly grew still. The next moment, Shining’s hoof was enveloped in her magic and shifted aside, and then Twilight rolled away. As Shining prepared to pounce on her again, legs tensing up, Twilight spun so her rear hooves were up against the wall, then launched herself at him, colliding into him and making him collapse on top of her.

“Nice one, Twiley,” Shining said, grinning. “But now you’re in trouble!” Already on top of her, he simply gripped her with his legs, pinning her once more.

“Nuh-uh~” she said in a singsong tone, before teleporting right out from under him. Most other unicorns would have found it difficult to pull off such a feat - teleporting while in direct contact with another living being was always tricky. But Twilight could not only do so with ease, but also have it so that when she reappeared, she was on her hooves again, facing him and ready to pounce. But, as she leapt, Shining Armor was ready, forming a shield between the two. Thankfully for Twilight, the shield was elastic, cushioning the impact as she pressed into it… before the shield sprang back in the opposite direction, flinging her away as though she’d ran headlong into a spring.

Laughing at the sight, Shining spun to face her, ready to charge - only for Twilight to conjure a wooden chest around him, sealing him in. “Hey!” Shining pounded on the chest’s lid, but it didn’t budge. “Now that’s just playing dirty!”

Outside, Twilight giggles. “Hey, didn’t you say once that you had to do whatever it takes to win a fight?”

“Were we fighting?” Shining chuckled. “I thought it was just a friendly sparring match between sessions. He grinned, before trying his own hoof at teleporting. But when he re-appeared, he was still in the chest. “Huh,” he said, impressed. “I see you’ve already mastered teleportation wards!”

“Well, I do have the best teacher in Equestria for protection spells!” Twilight beamed, even though Shining couldn’t see her.

“Well, thanks. But, do you remember what I said about what happens when two identical shields overlap?”

“Well, if the second unicorn can-” she began, but even as she spoke several things happened in quick succession. First, Shining Armor produced his own shield, right in the space that Twilight had placed her own barrier. In that instant, the two shields merged, both unicorns channeling power to it. Before Twilight could react to it, Shining used his own power to alter the combined shield, taking away the teleportation ward… and one teleport later, Twilight was once more pinned beneath him, the conjured chest vanishing as Twilight ceased maintaining that spell.

Twilight took a deep breath, winded slightly from the larger stallion landing on top of her. “Okay, you got me there.” She smiled. “I really wasn’t expecting that.”

Shining grinned, taking a little pride in magically besting her for once. “The biggest weakness of barrier spells - other barrier spells. Of course, usually it’s pretty hard to do something like that - the spells need to be very similar for them to actually merge like that. If the barrier is being produced by an artifact or something, and you have time, you can fine-tune your own barrier, but it’s much harder when another unicorn is maintaining it and can fight back.”

“You managed to do that pretty quickly, though,” Twilight’s eyes widened a little. It was a bit unusual for him to play the role of lecturer, but Twilight seemed to be taking it in with her usual fascination for all things magic.

Shining chuckled. “Well, that’s because your barriers are basically copies of mine, so our spells are pretty similar to begin with.

Twilight giggled. “Sorry for plagiarizing your work, Shiny.”

Shining laughed again. “Don’t be, you’re really great at learning spells just by encountering them, it’s actually pretty impressive.”

“Aw, thanks.” She smiled warmly up at him. “I’m really glad you approve, Shiny.”

Shining smiled in return. “I’m just glad you think I’m the best at barrier spells.”

“You are.” She reached up with a hoof and poked his chest. “We’re both gifted at magic, you know. I may be trying to learn every spell in existence, but you’ll always be better at protecting things.”

“Well, I dunno about that… I think you could do anything if you really put your mind to it, Twily.” He smiled a little wistfully, running a hoof through her mane. “But honestly, I’m fine with not being the best, as long as I can protect the ponies I love.”

Twilight smiled in return. “Don’t worry, Shiny. I know you can.”

They both leaned in to nuzzle the other, brushing their cheeks together… and then, by sheer coincidence, they both turned their muzzles to each other at the same time, so that the gentle nuzzling suddenly turned into a deep kiss.

Both of them froze. A bit of inertia, however, meant that their lips were still pressed together. It wasn’t the best kiss ever… but it was definitely a kiss... That they were holding. Each expected the other to suddenly pull back… but neither did.

Shining, finally, was the first to pull back, just slightly - each letting out a breath they’d been holding, the warm air passing over each other’s lips and making the moment even more unexpectedly sensual.

And then the door opened. Shining reacted first, standing up straight as their parents returned home.

“We’re ho-” Night Light began, before noticing that one of his children was already in the room. His view of Twilight was blocked by the couch, for the moment. “Hey, Shining.”

“Hey, dad.” Shining stepped off Twilight, who rolled onto her hooves and stood up. “Welcome home,” she said, a little too breathlessly.

“All you all right?” Twilight Velvet chimed in, close behind her husband.

“Yeah, I, uh…”

Shining Armor put on a bashful smile. “We were, uh, play-fighting before you came in.” He pawed the ground with a hoof. “Little embarrassing to be caught playing like little foals.”

Velvet just laughed. “As long it didn’t turn into a food fight this time, I don’t mind.” She glanced around the living room. “Honestly, I can’t even tell. The house looks pretty clean this time.”

Shining rolled his eyes. “Mom, not every sparring match ends with the living room being destroyed.”

Night Light grinned at him. “Might leave the house smelling of garlic, though.”

Twilight blushed. “That was a one-time thing! A Nightmare Night prank that got a little out-of-hoof!”

Her mom scowled at her, though her eyes still held a mischievous smile. “Yes, but it took me days to get the smell out, you know.”

Twilight sighed, smacking her hoof against her face. “I’m going to go back to studying.” She turned around, and started trotting back to the study.

Spike chose this moment to appear from the direction of Twilight’s bedroom. “What’s with all the noise?” he asked groggily - only for Twilight to grab him with her magic and carry him with her as she entered the study, shutting the door behind them.

Night Light chuckled. “Well, I’m glad you two had fun.”

“Yeah…” Shining Armor’s eyes fell on the paper that Twilight had dropped when he pounced on her. Obviously something she wanted to show him, but truthfully, he couldn’t understand much of it… but that didn’t stop him from trying. For her sake.

2: Practice

It didn’t bother Shining Armor as much as it maybe should have.

The two were not only close as siblings, but they were a lot more affectionate than most - perfectly fine with long hugs, nuzzling, and pecks on the cheek. They’d cuddled together on occasion, with Twilight curled up in Shining’s embrace. They’d even shared the same bed from time to time - though this had become much rarer as the two had grown. Given how much contact they made, it was surprising that such an accidental lip-lock hadn’t happened sooner. It was actually less embarrassing than the fact that their parents had nearly walked in on them.

So, as he settled in for the night, he hadn’t quite prepared for Twilight to come into his room. “Shiny, before you go to bed, can we talk about something?” She approached his bed, looking intently at him.

“Yeah, sure.” He sat up in his bed, suddenly concerned. “What is it?” he asked, despite knowing the answer. He’d thought she had taken it in stride like he had - she certainly hadn’t mentioned anything the rest of the night. Though, perhaps she just needed to gather her thoughts… either that, or she just wanted to finish studying first.

“Did you… enjoy what happened earlier?”

Shining grimaced a little - this was very much a question where the wrong answer could be disastrous. “I, uh… well, why do you ask?”

“I was just curious… I kinda liked it, so I wanted to know if you did, too.” Her reply was even and matter-of-fact, a tone Shining was used to hearing from her. But it left him unsure how to respond. She said it so… innocently. He wasn’t quite sure what was going on in her head.

“I… well, a little. I mean, it was just our lips touching on accident, it wasn’t really much of a kiss.” He chuckled. “There’s more to good kissing than just pressing lips together.”

“I see.” Twilight fidgeted slightly. “How… how does it work, normally?”

“Well…” Shining frowned. “Why do you ask?”

“I… thought it was nice, but if there’s more to it, I want to learn, so next time it’ll be better.”

Shining shifted a little. Being asked to explain how a kiss worked was not something he’d thought would happen to him. “Well… it’s kind of hard to explain. Have you looked in any books?”

Twilight frowned. “I have, but they kind of… gloss over the exact details. It’s really not the same reading about a kiss. The reality is… different.”

“Hmm.” Shining had to wonder if the books she’d consulted were sultry romance novels, something he had little experience reading. He was fairly certain she had a hidden stash of shipfics somewhere, at least. “I think it’s something you have to… learn as you go.”

“I see…” Twilight’s voice lowered slightly, but noticeably. “Can… you help with that?”

Shining’s eyes widened a little. “Excuse me?”

“Well..” Twilight blushed suddenly, looking away, but her voice kept its usual matter-of-fact tone.. “II mean, it’s not like I have anypony else to practice with - that was my first kiss, you know.”

Shining had assumed as much - Twilight’s dedication to her studies had its issues. “Yeah, but… it’d be kind of awkward…”

Twilight looked back at him, a sudden determination in her voice. “Shiny, you’re… well, you’re the only pony I’d feel comfortable doing this with…” She fidgeted, starting to blush. “I know it’s a little awkward for this to suddenly come up, but…”

Well, Shining had told himself that accidentally kissing her wasn’t that embarrassing, but doing it deliberately was somehow… different. Still… when had he ever passed up a chance to help his little sister?

“All right.” He shifted to make room for her on the bed, and she climbed in with him, smiling slightly as she lay on her side facing him. The two were pretty close, practically hugging each other, almost kissing even as it was.

“So, uh…” Twilight still blushed a little, but her breathing slowed as she started to relax. “Well, obviously I don’t know how to kiss properly…”

“All right.” Shining bit his lip. A part of him had been hoping he wouldn’t have to take the initiative on this. “Well, you… it’s… you kind of…” He tried to think of something to tell her, some bit of preparatory advice. But, just as he had said, it was really hard to explain.

So, he decided to just go for it.

Twilight let out a muffled little yelp of surprise as Shining suddenly pressed against her, her lips now covered by his. This wasn’t just simple contact - Shining took an active role, while going back and forth between gentle touching and stronger pressure. Meanwhile, he opened his mouth just a little, brushing his lips across hers before giving her a quick lick. Twilight seemed too overwhelmed to respond, just weakly pushing back against him. After a few long moments, however, he drew back, now blushing a little himself. “Something like that.”

“I… um…” Twilight was blushing even harder. “Let me try…”

This time, she pressed into him. As usual, she was a quick learner, repeating much of what Shining had done to her, although she didn’t experiment or vary her pattern much. Still… Shining had to admit it was an improvement. When finally she drew back, she took a deep breath. “How’s that?”

“Better.” Shining said, smiling a little.

“How about… with tongues this time?” She blushed even more, starting to show a side of her Shining hadn’t really seen. The only time she got this giddy was when she was reading a new, particularly good book, but that was still different than this. Though it felt weird for his sister to enjoy kissing him this much, he couldn’t help but feel some pride at being able to give her that much pleasure.”

“...All right, sure.” After a moment’s hesitation, Shining kissed her again, this time licking at her lips and pushing at the gap between them. She quickly took the hint, opening her mouth to allow his tongue in. He lapped around her mouth for a short while, occasionally caressing her tongue with his own.

When finally he drew back, both were lightly panting. Twilight didn’t say anything this time, just smiling at him before giving french kissing a try herself. Both of them went at it this time, their tongues constantly struggling with each other as they made out.

It was a long time before Shining pulled back, and he would have gone on even longer if it hadn’t been for something that had come to both their attentions. Namely, a very inopportune hard-on. His shaft had unsheathed fully, and even now the tip was pressing against her waist.

Shining blushed, both of them glancing down towards where their hips were nearly touching, although neither could actually see anything. Twilight giggled for a moment, before Shining interrupted her. “I, uh… think that’s enough for tonight.”

Twilight giggled even more. “Got something to take care of?”

“Hey!” Shining gave her a glare, though as always there was no real venom to it. “What I do in bed at night is none of your business.”

Twilight stopped her laughter and smiled. “Sorry. Thanks for… showing me kissing.” She spoke softly once more. “And… I’m glad you enjoyed it. Did I do well?”

“Yeah…” Shining chuckled. Pretty good for your first day of kissing.”

“I’m glad to hear it!” Twilight rolled off his bed and onto her hooves on the floor. “Good night, Shiny.”

“Good night, Twily.” Shining nodded to her as she quietly left the room and shut the door.

He spent the next few minutes in thought, too preoccupied to even jerk off. He’d gone into that a little too easily… and for that, matter, so had she. But… it felt oddly natural. It made sense that they could do something so… personal. He trusted her more than anypony else, and she certainly felt the same way about him. Enough to do something as silly as practicing kissing.

He chuckled, before settling into sleep. It really did seem silly, but who better to do silly stuff with? She was somepony he felt he could be completely open with, without feeling embarrassed. Maybe they’d laugh about this tomorrow… away from their parents.

3: Proposal

It was two days before they really spent much time together again. The following day had been a return to the usual, exhausting training routine for Shining, and Twilight had chosen that day to pay a visit to Cadance anyway. But the day after that was a weekend, and both Twilight and Shining had the day off. Twilight, as it turned out, had scheduled that afternoon for the two of them to spend some time together - studying, she said.

He figured something was up, however, when Twilight told him - after they’d left the house - that they weren’t going to go to the library, but instead to Cadance’s house while she was out. “She’s on a trip to Fillydelphia, and I asked her if I could use her place while she was away, in case I wanted to study alone.” She levitated a key up to Shining for emphasis, before stowing it away in her bags.

“You won’t be alone, though,” Shining pointed out, frowning a little.

“Well, alone with you, in this case.” Twilight smiled. “Besides, it’s more comfy there than in the library.”

Shining chuckled. “I won’t argue with that.” Still, he wasn’t clueless. Obviously, she had something she wanted to talk about, away from everypony else.

She did, however, bring along some books, and as they entered Cadance’s living room, she levitated them out of her bags and onto the coffee table, before taking a seat on a soft, plushy sofa. “Now, where to begin…” Shining sat on a couch on the other side of the table, watching as she flipped open a book on zoology and started taking notes.

It was obvious to Shining that she was distracted, however - if only because she was a little less on-the-nose than usual, taking slightly longer to turn pages or solve problems. For most ponies this was normal, but if Twilight wasn’t giving her full attention to her studies, if her mood was anything other than complete determination, then something else was on her mind. It was not hard to guess what.

Of course, since she was apparently using the excuse of studying to put off talking about it, it fell to Shining to take the initiative, again. “Something on your mind, Twily?”

She hesitated slightly, before setting down her pen. “Is it that obvious?” She smiled, just a little.

“To me, anyway.” He matched her smile. “I’m guessing we came out here because you wanted a private conversation.”

Twilight shifted, laying on her side, her head resting against a pillow at one end of the couch. She bit her lip, glancing away. It was actually kind of odd for Shining to see her at a loss for words, especially given that she’d planned this… so Shining decided to make it easier for her. “Is it about… us kissing the other night?”

“Kind of.” She smiled, looking at him. “I… liked it.”

“You liked it?” Shining titled his head slightly. “Are you… saying you want to kiss some more?”

Twilight glanced away again, blushing slightly. “I... really liked it, Shiny.”

“...I see.” Shining frowned a little, thinking. He asked himself how much he had liked it… and he didn’t really know the answer to that. He stirred himself out of his thoughts, and noticed that Twilight was looking at him expectantly, even nervously. He bit his lip for a moment before speaking. “Like… how, exactly?”

Twilight blushed even more. “Well… I mean, it felt good physically, but it also felt good… inside. I felt really light and excited and… safe. I mean, I always do with you, but… it was even more intense this time.”

“So…” Shining had a feeling they were both going to dance around the subject until one of them came out and said it directly. “Do you think you’re falling in love with me?” Despite the blunt statement, his voice was soft, and just a little nervous.

“Not… exactly? I think it might be that I always was in love with you.” Twilight sat on the couch, before looking at him in the eye. “I spoke with Cadance, and asked her what love felt like - I didn’t tell her about us-” she quickly added on seeing his expression. “I just wanted to know how somepony could tell if they were in love. She told me there were… a bunch of different kinds of love, and…” Twilight took a deep breath. “This isn’t me wanting you to sweep me off my hooves or anything like that. What it is, is that you’re the closest to me I could imagine anypony to be. I trust you completely, and I feel like we could do… anything together, without feeling bad about it. Even kissing… or more.” She blushed.

Shining took a moment to process this. “Well… Twily, I definitely trust you, and I do feel comfortable doing… just about anything.” He frowned a little. “...Sex is a little different, though.”

“Is it because we’re brother and sister?”

Shining just nodded.

“Why?”

Shining frowned. A simple question, spoken in a neutrally curious, almost innocent tone. Twilight was like that sometimes - often the books she liked to read were matter-of-fact, and without any overt judgements, and sometimes this meant she understood something only in terms of hard data - without any kind of personal feeling one way or the other. Sometimes it kept her objective. Other times, she needed to be told why something was bad.

He also wondered if some of the romance stories she’d been reading had desensitized her to the concept. Especially the fanfiction. There seemed to be a lot of incest in fanfiction, for some reason.

“It’s… well…” Shining’s brow furrowed in thought. “Part of it’s because… inbreeding isn’t good.” He struggled for a moment to remember the technical details of inbreeding, but he found he actually didn’t know much beyond a general impression that it was something to be avoid. “It’s… something to do with genetic defects?”

“There is an increased risk of genetic defects, such as when both parents possess a rare, recessive trait and then produce a child with two copies of that trait...” Twilight’s horn lit up, and she produced a small family tree out of light to illustrate her point. “But that’s why inbreeding is frowned upon, not incest itself. Or romantic relations.” Twilight shook her head, dispelling the diagram.

Shining sighed. “I guess… it’s more of a feeling, then. Most ponies don’t like the idea of it.”

Twilight frowned. “How do you feel about it?”

“You mean, how do I feel about you?”

Twilight nodded without saying anything, and Shining looked away, likewise silent for a long moment. He glanced back towards her, and saw her still looking at him, waiting - almost desperate for his answer. So with some effort, he turned back to face her fully. “Well… I’m not really sure. I… well, I haven’t thought about going all the way, but to be honest… I’ve always been pretty comfortable hugging you and… even kissing you wasn’t as weird as I thought it would be.” He frowned. “What do you really want, though? I mean, in terms of us, of how our relationship should be?”

“Well…” Twilight chewed her lip for a moment. “I realize we can’t just be like a normal couple, and that’s not what I want anyway. What I want, Shiny, is…” She looked down, blushing. “Well… I’m probably not going to find a coltfriend anytime soon, and you’re closer to me than I could ever imagine another colt being, anyway… so I want to be able to share in that part of life. Of… having sex.” She looked back up at him. “I mean… that’s the main difference between us and a married couple, when you really get down to it...”

“Speaking of couples…” Shining glanced around, at the room itself. Cadance’s living room. “You know I’m…?”

“Yes, I realize that you and Cadance are… a thing.” She blushed. “But, she’s strongly implied she would be okay with you being with other ponies, if you loved each other.”

Shining nodded. Cadance had been more explicit with him - she didn’t condone one-night stands, but she respected love in all its forms, and didn’t like stepping in the way of such bonds. He wasn’t quite sure what she’d think of this… but she had teased them more than once about how close they were. He started to wonder if she had let the pair use her house, knowing that something like this would happen. He wasn’t the only one good at telling what was going on with Twilight, after all.

In any event, she had a point. They did seem like a couple at times. He’d certainly heard at least one pony mistake them for a couple when they were out in public. But more than that… there was something endearing about how she was, essentially, asking him for help.

Still... it all came down to whether or not he wanted to have sex with his own sister.

He got up and stepped off the couch, circling around the table to where Twilight sat. She perked up a little as he approached, then sat beside her. He took a deep breath and said, “Let’s… try something first.” Then, he kissed her.

Her reaction was immediate, letting out a happy little sound that made Shining feel both a bit of shame and a bit of a thrill. The latter feeling won out, and he pressed in, kissing her more forcefully while he wrapped a hoof around her, pulling her tight against him. She responded in kind, sloppily pressing her lips back against his while opening her mouth. Shining licked at her lips before sliding his tongue inside, and she let out a moan as her tongue pushed at his.

After a solid minute of kissing, Shining pulled back. “Now… do you want more of that? Are you really comfortable going all the way?”

Twilight’s rapid breathing and the warmth in her eyes told him the answer before she spoke. “Yes!” She cleared her throat, blushing. “Yes, I do.”

Shining looked at her for a long moment. There was one last thing holding him back, and that was the fact that, if they did have sex, it would change things. Even though they were definitely closer than brother and sister as it was, he knew that if they had sex and enjoyed it, it would change how they saw each other. Every time he looked at her, there would be that faint touch of desire, of knowing that they’d had sex and could do so again. When he heard her voice, he’d know how it sounded when she moaned in pleasure, and every time he touched her there’d be the faintest of reminders that he’d felt her body up against his while making love. If they had sex, it would no longer just be a platonic relationship.

But then again, maybe it was already too late for that.

“All right,” Shining said, scooting to the side to give her some room. “Lie down on your back, and spread your hind legs a little.”

Twilight nodded, eagerly doing as he said. Her breathing picked up, a blush forming on her cheeks as she looked at him. Meanwhile, Shining looked down at her, where her entrance was. He’d seen it before, of course, but never when she was aroused and eager to have sex with him. He could, however, see that it needed some work… and he leaned his head down and gave her nethers a lick, eliciting a gasp from his sister at the sensation.

Shining chuckled. “This is foreplay, Twily. Very important for your first time…” He paused to give her a few more licks, before going on, “Your first time should be memorable, after all.”

Twilight nodded, trying to hold still, though her leg twitched as he continued to go down on her. She closed her eyes, trying to control her breathing with deep breaths, as her pussy grew wet and started to wink. At last, Shining pulled back, straightening up - and giving Twilight a view of his fully-unsheathed cock. “You ready, Twily?”

Twilight nodded. “What about you? Should I… do some foreplay for you?”

“If you’d like. Don’t worry about that though, just focus on enjoying yourself.” He smiled at her.

Twilight blushed in response. “Thanks, but… I want to have the full experience.”

“All right.” Shining stepped forward, carefully making his way over her until his shaft hung over her face, while he rested his hooves on the couch’s hoofrest. Twilight looked at his stallionhood for a long moment - the first time she’d really examined it while it was unsheathed and eager to penetrate a mare. After moving her head around to look at it from different angles, she reached her hooves up, holding it in place while she gave its tip a few licks.

Shining chuckled a little at her inexperience, as she went about foreplay in her usual methodical way. “Why don’t you try taking it in your mouth, if you’re ready for that.”

“S-sure…” Twilight lifted her head up as best she could, wrapping her lips around the tip and gently sucking on it. Shining let out a satisfied sigh, lowering his hips slightly so she could rest her head on the couch again. Twilight spent the next few moments gently suckling him, before starting to grow bolder, licking at his tip before lifting her head up again, trying to take him in deeper. She managed to go halfway up his shaft before pulling back, before settling for bobbing her head back and forth along his length.

Shining let out a soft moan, before gently started to pull up off her. She wasn’t bad, but she was still inexperienced, and right now she was pretty much teasing him… which meant that now he was definitely ready to rut her. He backed up, getting into position above her, before lowering his front a little to give her a quick kiss. “Are you ready, Twily?”

Twilight nodded. “Yes… please mate with me…”

Shining chuckled. Even like this, she was clinical in her language. “All right.” He pressed forward with his hips, the tip of his cock spearing her entrance and pushing into her. She gasped, and cooed lightly as he filled her. To his surprise, she wasn’t quite as tight as he’d expected - he wondered for a moment how often she used certain “toys” of hers, before he pulled back slightly and the pleasure banished the thought from his mind. He pushed in again, letting out a grunt, careful not to go too deep or too fast.

Twilight moaned and gasped, but didn’t move - something Shining noted. “How’s it feel?” he asked.

“Pretty good…” She smiled at him, eyes lidded.

“You don’t have to hold still, you know. It’ll feel even better if you take part, too.” He returned her smile, before leaning town to brush his lips against hers.

“O-oh, sorry… let’s see” She gripped his barrel with her hind legs, weakly trying to buck her hips up into him. Shining thrust into her in response, timing the motion so that it was right as she bucked upwards. She gasped, “You’re right…”

Shining leaned in to kiss her again, before resuming his pace. Twilight wrapped her hooves around him, holding him close as they kissed, his thick shaft grinding inside her. He took it slow for a while, letting her get used to the new experience - and giving them more time to kiss and cuddle while they made love.

After a while, Shining straightened up and picked up his pace. He smiled down at his sister, and her glazed, pleasured expression. If she seemed distracted before, now she was mentally all but gone- no analytical thinking, no logic, no learning. Just pure, loving bliss. The thought made him flush with pride, and he leaned in to kiss her again, ready to give her everything she deserved.

“Shiny… I’m coming close…” Twilight gasped, clinging even more tightly to him. “Please… orgasm inside me…”

Shining couldn’t help but laugh a little. “It’s okay to cuss, you know. Come on, I want to hear you say it without sounding like a textbook.”

Twilight blushed. “Please… fuck me, Shiny! Cum inside me!” Shining didn’t even get a chance to respond before she kissed him hungrily, refusing to let him break the kiss. Shining couldn’t hold himself back any longer, and he slammed his hips into her, pressing forward as he started to cum inside her.

Twilight squealed, but didn’t break the embrace or the kiss. She let out a muffled moan as she started to shake, holding on to Shining as he pounded her, filling her up with his cum. It seemed like an eternity before they both came to a stop. Shining broke the kiss, looking into his sister’s eyes as she looked into his, both of them panting. Another eternity passed before either of them spoke.

“How… how was it?” Shining smiled, a little nervously.

“Amazing…” Twilight smiled up at him. “You did a really good job, Shiny…” She lifted her head up to give him a quick peck on the lips. “And, thank you… you’re the best.”

Shining returned the kiss, feeling a warmth build up in his chest. “I’m glad.”

Twilight yawned abruptly. “I’m tired all of a sudden…”

Shining chuckled. “Probably more exercise than you’ve had in a while, huh?” He stood up, taking his weight off her, pulling out of her in the process.

“Mm, I should work on that…” She rolled over onto her stomach, heedless of the cum spilling out of her pussy. “Hey, Shiny… can you lie here with me?”

“For you, little sis, anything. Not much room on this couch, though… I’ll have to get pretty close” Shining settled back down onto her, covering her protectively. “You don’t mind, right?” He smirked.

Twilight snorted. “That’s perfect, thanks…” She closed her eyes, settling into the softness of the couch.

Shining kept his eyes open a little while longer. He wondered if he’d regret this in the morning… but he was pretty sure Twilight wouldn’t. She rarely had regrets like that, not when she was pursuing something she wanted. The worst that would happen would be that she’d consider it “a learning experience.” At best… well… they were now lovers too.

Shining smiled. She was happy, that was what was important. He’d never regretted making her happy.

Author's Note

Aaaaand there you have it. My take on my favorite of incest ships, Twilight x Shining!

Planning this was actually kind of a challenge, and not just because I was working on a two-week deadline. I wanted to try my own take on the ship... which is sort of difficult when you already have a headcanon for this ship, and it's in the form of existing fics (Like Two Peas in a Pod by Flutterwhy4 and Complicated Relations by Softy8088, if you're curious). So I kind of had to come up with something else that I liked that, that I would consider headcanon if I didn't already have a headcanon, preferably something I hadn't really seen before. This is the result.

As mentioned, this was written for the April 2019 Incest is Wincest contest, which I took as an opportunity to break my writer's block... as well as give myself some needing confidence, by proving that I could force myself to write under a deadline. After a lot of effort and procrastination in equal measure, I think I've succeeded!