Rainbow Dash grumbled while Twilight looked at the sign in front of them. The lack of moving lips hadn’t been too much of a bother, and apart from that one set of alluring rubber socks -- or stockings, she wasn’t sure of the proper term -- she hadn’t really felt like buying anything at the Coursers and Corsets Erotica Convention. The need to speak hadn’t been all that pressing so far.

But eventually, both the royal alicorn and the red and black fake alicorn had reached the most popular stand of the convention, the one stand where every visitor, even the most timid and prudish, would make at least one small purchase: the food stall. This was the place where even the most dedicated of pets had to take off their gags and open their mouths. Either that or go hungry, which no self-respecting dominant allowed to happen to their pets.

How anypony managed to overpower the scent of rubber and arousal with the scent of apple fritters and donuts was anyone’s guess, but the big barracks in front of the pair managed it somehow. Wide enough to serve three rows of primarily black and red rubber alicorns, as well as three Celestias and four Nightmare Moons, the ponies doing the cooking were a true rarity at the convention, in that they were the only ones not clad in rubber.

The ponies were also a rarity in that they were not ponies, but changelings. Rainbow Dash waited as Twilight finished reading the signs in front of the stall.

“Well, this is interesting. So apparently, these guys are solitary changelings living in Equestria, all registered. And since they don’t have to hide their identity with rubber, they’re the ones behind a hot furnace, instead of ponies. I guess their skins can take the occasional splatter. Good way to get them integrated, I guess. How did they get in here with nopony noticing, though?” Twilight turned her head towards her silent companion, who just pointed to Twilight, then back to herself.

Twilight tilted her head back as it sunk in. “Right, same way we did.”

The line moved on, and Rainbow heard the subtle clopping of a pony in stilts as the Nightmare Moon in front of them got ready to give her order. “The Grand and Potent Nightmare Moon would like seven apple fritters and a glass of grape juice, if you please.”

Rainbow suddenly felt glad her lips had been sealed by that post-hypnotic suggestion. Even if the Nightmare Moon costume was a good replica, that kind of talking sounded too familiar to not be noticed. Twilight held up a hoof to her mouth to stop from laughing herself. She lowered her voice to a whisper, barely audible above all the clopping of the rubber alicorns looking for a seat. “Did you just hear that? You don’t suppose that’s… no, it couldn’t be. She wouldn’t talk like that, not here.”

Their turn came. Twilight ordered apple fritters for two, with some milk to go along with it. After paying and getting her wares, they went looking for a seat where Twilight might unlock Rainbow’s lips.

“The Great and Powerful Nightmare Moon would like a packet of honey-roasted almonds and a cup of coffee, if you please.”

Twilight and Rainbow Dash froze, before turning to the other Nightmare Moon who was now getting nuts. Twilight shrugged, eliciting a squeak from her rubber costume. “Okay, that one might be.”

They found a seat someplace private. Rainbow Dash settled down with a soft moan, still relishing the feel of the rubber against her sensitised fur and nether regions. Then her eyes caught a different kind of food stall, and her mouth struggled to keep her laughter in against the suggestion.

Rarity absent-mindedly cleaned her dishes after lunch. Even as the spell animating the sponge kept it scrubbing, her mind kept on turning to Rainbow Dash and Twilight.

They said they’d be going to Baltimare. Plenty of conventions happen in Baltimare. There’s no reason to think anything strange of that.

Then again, Rainbow Dash seemed awfully distracted. Cloud Kicker and Raindrops can’t be that hard to train, can they? They’re adults, they must be progressing just fine on their own. And then there is Scootaloo.

Poor thing, not knowing if she’s handicapped or not. Oh, nonsense, Rarity, of course she’s not handicapped. Twilight managed to slap wings on you, after all, there’s no reason to think a proper doctor can’t fix whatever is keeping that girl on the ground.

She stopped her train of thought, and the sponge. With a mutter under her breath, she summoned a kitchen towel to dry the last dish off, then neatly completed the stack of dishes in the cupboard.

You’re being silly, Rarity, and evasive. Rainbow Dash has a lot on her mind, that’s all. Twilight is probably helping her get more organised, maybe help Rainbow take care of Scootaloo like a proper big sister, or even give her dating advice.

Rarity pulled the plug from the sink and strode off to the main room of her shop. There’s a thought; suppose Twilight is helping Rainbow Dash fetch herself a stallion? Rainbow did mention Thunderlane once or twice, perhaps she’s finally found a new paragon?

Yes, that must be it. The fake Cadence gave all of us advice at the royal wedding, when she didn’t know what she was talking about. That’s why Pinkie’s Pinkie Sense went off: Twilight always knows what she’s talking about, except when it comes to stallions. That particular combo must happen when someone is pretending to know what they’re talking about, and Twilight was just hiding her ignorance for Rainbow’s sake. They’re off to Baltimare now to acquire some proper literature, no doubt.

Rarity bit her lip as she regarded some of the items lying ready for pickup.

And if not, I suppose I’ll just have to explain why I added edible boots to my collection.

Twilight eagerly picked up another book and leafed through it, careful to use her hooves and not her magic this time. Rainbow Dash sighed in her rubber confines and browsed the stall herself. We’re gonna be here a while.

Rainbow’s eye wandered to Twilight’s saddlebags. They looked more swollen than she remembered, but then Rainbow hadn’t been keeping too close a track on what her Mistress was buying.

Twilight looked up from the book she’d been checking, to see her pet staring out into the crowds. She turned to red and black alicorn vendor number 57 (and counting). “Excuse me, sir, I don’t suppose you have any books aimed at the athletic crowd?”

The pony in rubber nodded emphatically and pointed to a corner on his, or her, far left. “Certainly, Madam. We have a section dedicated to the jockification fetish, as well as some practical guides on flexibility.”

Twilight prodded Rainbow Dash and pointed to the same corner. Slowly, rolling her eyes, Rainbow checked some of the books on offer. There were discounts and group buy offers littered around the table, most likely because there wasn’t much of a market for athletic dominants or submissives.

Still, Rainbow checked out one book that caught her eye: “Your Perfect Jock: Fitness in Sexual Pets.”

Okay, index looks promising. Looks like it’s got tips for all three races, good. Exercises… ooh, so that’s where those muscles are. I can get a tennis ball easily enough. She leafed through it some more. Huh, it’s even got tips to keep your libido up after cardio, that’s right up my alley. Wait, was libido being horny or slipping a disk in your back? Pretty sure it’s got to do with sex. Well, either way, this one’s a keeper.

She skipped the surprisingly numerous erotic fiction lying around with athletes of varying stripe as the protagonist -- or antagonists, depending on one’s point of view and relevant local legislation -- and went straight for the next book: a flexibility manual, geared specifically towards sprinters and stunt flyers, like her.

And this one… oh, this one’s pretty good, too. Wow, they don’t teach those stretches in the Wonderbolts. Ooh, and isometrics? I’ve been looking all over for this stuff.

Twilight, true to form, had already found the dozen or so books she’d been looking for by the time Rainbow Dash had decided she rather liked the pair she’d found. Rainbow Dash gestured to the two books, and with some minor management from her Mistress, Rainbow Dash made her first two purchases at an erotica convention.

The completely stuffed state of Twilight’s saddlebags at this point caused her only a minor degree of concern.

“Well, pet, did you see everything? Got what you wanted to get?” Twilight led the way towards the exit.

Rainbow Dash suppressed a sigh. Those rubber socks are still there, waiting for me. I should’ve said something at lunch, but… nah, I don’t really need to get those right now. They are kinda expensive, even if they would feel nice. She nodded and followed her Mistress without hesitation.

They went into the contraption to get changed. Twilight first dispelled her own second skin, then slowly peeled off the temporary rubber from Rainbow Dash’s body, grinning to herself as she went.

Rainbow Dash moaned, still keeping her lips together. Her ears twitched as the cool air touched them once more, her head was positively throbbing from the warmth the suit had held. Then the suit dissipated around her marehood. The mere touch of air, the softest reassurance she was bare again, sent tingles up her spine that settled into her wingtips just as they too were exposed.

Twilight placed her lips on Rainbow’s mouth again, gently giving her a lick as she touched her pet’s forehead. “Dive down deep, pet.”

Despite it all, Rainbow couldn’t help but surrender to the heavy comfort of obedience. She still felt insanely aroused, but she couldn’t do anything about it, not without Twilight’s approval. The alicorn gently rubbed along Rainbow’s lips. “Feel the glue around your lips dissipating now, letting you talk freely and openly. Your lips are unsealed, your throat is free to speak. Can you talk again, pet?”

Just being called ‘pet’ made Rainbow quiver in her nether regions. She clenched her eyes shut, hoping to hide it. “Yes, Mistress.”

Twilight ruffled Rainbow’s mane. “Excellent. Now you can wake up, we’ll catch the next train headed home, and we’ll be back in Ponyville in time for dinner.”

Rainbow Dash rubbed her head as the trance subsided. “Sounds good, Twilight.” She caught herself saying it. Twilight. I’m listening to Twilight now, she’s not Mistress. We’re not playing right now.

They went out with their things packed in their saddlebags, hidden from prying eyes. Once past security, no one would ever know they’d been to an erotica convention. Rainbow patted her bags with her wings, just to check if their contents were still there. The books felt heavier than the ones she’d read, making her think she’d only gotten her hooves on a lighter version, or a safe one. And if that was the safe parts, what kind of other stuff is in there?

Twilight looked at said bags. “Got some interesting books?”

The pegasus pony looked around for anyone listened and lowered her voice. “Um, yeah. Something about being a jock and a pet, and something about stretches. The one on stretches looked really good just for normal stuff, too; I get this twitch sometimes on really small muscles near my wings, it’d be nice to know how to fix that.”

Twilight nodded. “I’ll bet. So, um, did you enjoy today? Being with me, I mean?”

Rainbow bit her lip and suppressed the urge to grin in public. “I’ll tell ya when we get on the train.”

Rainbow Dash checked the clip on her saddlebags after checking her books for the umpteenth time. Twilight checked her bags as well, and promptly placed all the bags under their seat.

They looked in front of them, they looked behind them, they looked to the sides. The train car was completely empty. Rainbow Dash twitched in anticipation. “You know what’s gonna happen next.”

Twilight shuddered. “Yup.”

As one, they burst out laughing. Rainbow fell over on the seat, landing with her head on Twilight’s lap, though she would deny it being on purpose. Twilight didn’t care, as she was too busy trying to cope with the severe case of the giggles. “Oh my, I have to admit I did not think it would be quite like that.”

Rainbow let out one last chuckle, kicking her hind legs with glee. “You knew there’d be rubber alicorns there. You knew you’d blend in perfectly.”

Twilight blushed. “I did read up on it, yes, it’s basic etiquette. You didn’t mind, did you?”

“I don’t mind a good prank, Twilight, and that was a really good one. And it was funny to see you finding that dildo, too. Is that really, you know…”

Twilight looked around again, just as the train left the station. She looked flabbergasted. “I honestly think it is, but I don’t know how. I don’t think it really matters if it is, there’s no reason to bring it up anywhere. And hey, it’s only for science. It’s not like I’m doing anything illegal or incestuous.”

Rainbow mentally noted the distinction Twilight seemed to make between breaking the law and making love to her brother, but she didn’t voice it. She was still reeling, and laughing. “No. It was really interesting to see all that, and we got some good books. Even stuff I’d want to read.”

Twilight gently petted Rainbow’s mane. “So… you had fun today?”

Rainbow Dash looked up to see the doubt forming in her friend’s, her Mistress’s, eyes. “I had a lot of fun, Twilight, and I’m happy you got some good stuff out of it.”

Twilight chuckled. “So you are okay with me being, you know, like this? A dominant?”

“You’re not just dominant, Twilight. You’re my friend, more than my friend. You’re the only one I know I’d want to rest my head on like this.” Rainbow nuzzled upwards into Twilight’s belly. They could both feel the warmth growing in between them. “I don’t really know what it is between you and me, but I want to keep it. And even if I can’t, I want you to be happy. Are you? With me, this?”

Twilight bit her lip and chuckled again. “Happier than I’ve felt in a long time. It’s just that…”

“What’s the matter?”

Twilight closed her eyes and sighed, before forcing herself to look at Rainbow’s face again. “If we’re going to be together, then eventually we are going to end up making love to one another, for real. Not just trying to get each other off to clear our heads, but real, loving, sex. Are you sure we can do that?”

Rainbow reached up and stroked Twilight’s neck, gently going over her mane. “Of course we can. Why wouldn’t we?”

“W-well, it’s just that-”

“Mistress?”

Twilight froze.

“Is that what’s scaring you? That you’d have to put me in trance to make love? That you being what you are would get in the way otherwise?”

Twilight gulped. “It’s bad enough that I masturbated you with hypnosis, Rainbow Dash. The idea that I’d do it to actually make love, it just feels like rape.”

“So don’t, then. Like we promised: it has to be fun. I’m still getting the hang of being a good pet, you’re still getting used to being my Mistress. We’re both still getting used to liking mares. One fap, err, flap at a time, that’s how you learn to fly.”

Twilight giggled like a little school filly. “You did that on purpose.”

“It got a laugh out of you, didn’t it? Read up first if you’re scared, Twilight, see how other ponies do it. I wouldn’t mind making love in trance, if it means I get better at it. Isn’t that what you wanted? To have it be perfect, just the way you wanted it?”

Twilight blushed and turned her head away from the head on her lap. “Well…”

Rainbow Dash lowered her voice to a seductive whisper. “Don’t you feel hot just thinking about me licking you, stroking you? You know being controlled holds me back, just waiting for you to give the right command... I’d go really slow, and really try hard to do it just the way you like it.”

Twilight grumbled. “Now you’re just teasing, pet. It’s not proper.”

“Sorry, Mistress. But you get my point, don’t you? It’s okay to be scared of hurting me, but you shouldn’t be scared of just talking about it, or doing something harmless. It’s not rape if I get a choice.”

“Fair point. I suppose I’ll just have to brave it when I get there. Thank you, Rainbow Dash, I needed that.”

“No problem.” Rainbow sat up again and wrapped an arm and a wing around Twilight’s back. “That’s what I’m here for.”

Twilight pondered it for a moment, just as the train hit its first stop. No passengers boarded, they were still alone. “Come to think of it, Rainbow, we haven’t really vocalised our affections, have we?”

“We haven’t whatnow?”

“I love you, Rainbow Dash.”

Rainbow chuckled. “I love you too, Twilight Sparkle. There, does that feel any better?”

Twilight checked herself. No elevated heart rate, no blush, no ears warming up. Compared to changing species (twice), declaring her love was proving to be quite the letdown in terms of physical feedback. She grunted. “Not really. I was expecting that to be somewhat more impressive.”

“Well, what do you want? I’m not big on words, I never have been. I don’t see why it makes a difference if we say it. It’s not like we don’t know by now.”

Twilight looked out the window at the passing landscape. “Maybe. Or we’re just deluding ourselves and each other.”

“Twilight, if you really want to be sure, then you’re not gonna know just with me saying I love you. You know I’m more of a physical kind of girl.” Rainbow Dash turned Twilight towards her. “Do you really need to be sure, right now?”

The alicorn gulped. “Yes, Rainbow Dash, right now I really need to be sure if what I’m feeling is real. I just spent the better part of a day surrounded by ponies in rubber, and as funny as it was, I could use some normality right now.”

Rainbow nodded and smiled. “Okay. So now it’s your turn to let go and relax.” She let her hooves go over Twilight’s shoulders, then settled on the upper arms to pull her Mistress closer. “Have you ever kissed anypony? For real, on the lips?”

Twilight whimpered, her nose curled at the breath of warm air coming from her pet. “N-no. I don’t know how to do this, I’ve never done this. Why are we doing this?”

Rainbow looked Twilight straight in the eye. “You wanted to know. Do you still want to?”

Twilight took a deep breath to steady herself. Rainbow Dash waited patiently for the nod to come.

Then they kissed. Rather than the sloppy licks she’d used to seal Rainbow’s mouth for the convention, Twilight kept her tongue going around Rainbow’s lips, occasionally giving the mare a subtle nip.

They broke away and gazed longingly into each other’s eyes. At least, that’s how Twilight’s mind worded it, due in no small part to a steady diet of teen romance novels when she was young.

Rainbow smiled. “And? Happy now?”

Twilight checked herself again. Her heart was beating more loudly, her face felt warm, and the tips of her ears were throbbing. Not quite the same as her ascension, but a good feeling nonetheless. “Yes, very. It does feel more… real now. Thank you, Rainbow Dash.”

“No problem. Now put the book down.” Rainbow’s expression hardened.

Twilight’s ears flattened. “Um, what book?”

“The one you’re holding behind my head, the one with the section on kissing. I can see the reflection in the window over there. Just put it down.”

Twilight groaned and let the book float back into its bag, not breaking her hug. “Fine. But I was just trying to make sure I was doing it right!”

Rainbow chuckled. “I understand. It was good. But next time, don't use your tongue so much, it’s kinda messy.”

That got a resigned nod from the princess. “I noticed. I hope that won’t happen when we make love again.”

“Don’t worry about it. My cloud home’s easy to clean, and it’s big enough for the two of us if we ever go live together.”

Twilight raised an eyebrow. “What makes you sure I’d be moving in with you, and not the other way around?”

Rainbow smirked. “Um, you live in a library?”

Twilight shrugged. “So?”

“That’s a public building.”

Again, Twilight shrugged. “I still don’t get it.”

“You can get arrested for having sex in your house, Twilight.”

No answer came. Twilight just stared straight ahead.

Rainbow smirked, mentally marking them as even on the prank department. “You know, if you ever do tell princess Celestia about this, she’s got about as much explaining to do as you do, doesn’t she?”

Author's Notes:

I'd like to take this opportunity to thank my friend Yuki for convincing me to go to the F.A.C.T.S. in Ghent a while back, the only real con I've ever been to aside from gun expos (my dad needs a mule sometimes for his merch. I'm close enough). To be perfectly honest, I do feel I could have gotten more stuff, but I wound up only getting some Magic cards. I kinda regret not getting the Bamboo tablet Wacom was premiering, or whatever it was they were doing. I'd be lying if I said that's where the sock thing came from, but I'd be lying even more if I said it did nothing to inspire it.

Anywho, at the con, Yuki introduced me to some of her friends. One of them was in Asuma cosplay. I warned him to be careful, because I'd seen at least two Hidans around. He got out his cardboard blades. Gotta admire a guy for going the extra mile. There were also enough Narutos to reenact a fight scene from the series. Suffice to say, some of those experiences shone through for this trilogy, including the crowds at the food stalls.

Changelings are in this because I can't really make a statement about Equestrian sexual ethics without including them, and it also means Rarity's first assessment of the Pinkie Sense was right on all counts except the marriage one.

Yes, there is a hypnotic jockification fetish. Yes, I have it on good authority it is indeed not a popular fetish. The Dutch word 'lumbago' refers to a back injury, thought it might be funny if it was a technical term in Equestria, too.

As for Twilight still being insecure, keep in mind she's getting to grips with identity in general. Species changed twice in a short amount of time, a lot of insecurity, and on top of that she learns she's a sexual deviant (as in deviating from the norm) when before she'd never really considered herself a sexual creature. That sort of thing takes time. The difference between Twilight and Rainbow will be addressed more later on, too.