“Are you sure about this, Twilight?” Rainbow Dash squirmed and shuffled her feet as she stood in the library entirely naked while her bookish friend shamelessly leered at her.

“Of course I’m sure, Rainbow. Besides, you’re the one who brought up the idea first.” Twilight smiled and held out a quartet of odd, shiny blue socks for Rainbow.

“Yeah, as like, a neat thing to daydream about or maybe talk about in private, not… you know.” Rainbow put on the socks without complaint, blushing as she knelt down on the rubber paws and pulled the socks up, her lower legs pressing against the back of her thighs and disappearing as she pulled the latex over them. She blushed a bit deeper as she put her hands on her shoulders and let Twilight help her into the other pair of socks, the second set of squishy blue rubber paws covering her elbows as her arms were covered in tight latex and secured in the otherwise useless position much like her legs.

“Have I told you how cute you look in those?” Twilight smiled and ruffled her hair.

“Only every time I put them on.” Rainbow rolled her eyes, but didn’t blush any less.

“Good. And you’ll look even cuter with this.” Twilight’s smile sharpened slightly as she pulled a rubber muzzle from behind her back.

“Uh-uhm, are you sure that’s necessary this time? I mean, the paws are one thing but if ponies see me with- hey!” Rainbow squeaked as the muzzle shot towards her face, the rubber ring gag forcing itself into her mouth before she could fully close it and forcing her to leave her tongue hanging out to be comfortable. “Ahn nah eeehie eshehwy?”

“Now now, Rainbow. Those don’t sound like dog words.” Twilight giggled, giving her friend a playful flick against her ear.

Rainbow whined, her ears pulling back as she blushed deep red. “......arf. Arf waff ‘ark.”

“That’s better. Such a good puppy.” Twilight rewarded her with some pets and scritches before floating over a small bag, pulling out a fancy purple and gold collar with a polished bone-shaped tag dangling from it that had “Dashie” written on it in rainbow letters.

Rainbow blushed and whined again, but couldn’t quite hide a pleased smile even through the mask, slowly raising her head to present her neck to Twilight, her tail swishing slightly as the collar clicked shut.

“There we go. Almost done, only the special surprise left.” Twilight walked over to one of the shelves and magically floated a box from the back of the highest shelf.

Rainbow watched curiously as her friend spent several moments unlocking the box both magically and physically only to pull out… a pair of stickers? She turned her head to keep watching Twilight walk over to her back and press one of the stickers right over her cutie mark before casting a spell that made her flank tingle. When Twilight let go the sticker was sitting flush and practically indistinguishable from the cutie mark it was covering, now showing a picture of Rainbow’s collar complete with the name tag. Another tingling told her that Twilight had done the same thing on her other side.

“Rrrf arr waf?”

“Don’t worry, they’re completely harmless and should come right off with the right spell. Even if something does go wrong, the enchantment would wear off on its own within a few hours and the sticking spell should run out of power not that long after, so by tomorrow they’d just be falling off on her own.” Twilight hummed, inspecting Rainbow’s butt closely and giving it a few pokes before seemingly being satisfied. She moved in front of Rainbow again, floating over a familiar leash and clipping it to her collar. “Now, how about we give them a proper test run?”

Rainbow whined and blushed, dragging her hooves - or rather her paws - on the way to the door before steeling her resolve. She was Rainbow Dash, not afraid of anything, and more importantly she trusted Twilight. If not with everything, then at least with anything relating to magic and with Rainbow’s… secret hobby.

Slowly shuffling out of the library with its closed curtains, Rainbow squinted and blinked against the afternoon sun, almost falling on her face as she tried and failed to bring a hand up to her eyes. A tug on her leash made her start moving again and by the time her vision had adjusted they were already out on the street and heading deeper into town. Rainbow slowly turned her head left and right, blushing when ponies looked at her in passing and squirming when they simply kept walking without comment, seemingly ignoring her.

The growing noise from up ahead made her pay attention to her general surroundings again and her ears pinned back as she realized that Twilight had walked her all the way to the market, and was leading her to a very specific stall. She whined and tried to dig her paws in to make Twilight change course, but it was already too late. Her pupils dilated in mortified embarrassment as she watched Applejack step out of her family’s stall and walk right towards them.

“Hey there, Twilight! Anythin’ Ah can do for you?” Applejack stopped just a step or two in front of the unicorn, giving her a guileless smile.

“Thank you, Applejack, but I’m just out for a quick walk before heading to Pinkie’s for the party.” Twilight smiled right back as if butter wouldn’t melt in her mouth, completely ignoring Rainbow’s predicament like the jerky mean jerkface she secretly was under that hapless dorky nerd act.

Applejack on the other hand, had noticed Rainbow’s sounds of distress and turned her head to look right at her. “Awww, and hello to you too, Dashie. Ain’t been meanin’ to ignore ya, girl. Have y’all been a good gal for Twilight?” She stepped forward and leaned down, grabbing Rainbow’s face with both hands to squish and rub her cheeks before ruffling her hair and scratching her behind the ears.

Rainbow froze, completely bluescreening and nearly cumming right there on the spot from her friend’s actions. Her tail started wagging and she let out a few instinctual yips, tongue hanging out and panting softly as she leaned into Applejack’s hands with a shudder.

“Golly, she sure is eager for pets today. Y’all ain’t been neglectin’ her over one of yer books again, have ya Twi?” Applejack looked up at Twilight, still ruffling and petting Rainbow’s mane.

“Gosh, I hope not, but you know me.” Twilight giggled. “Still, I think she’s just excited for the party. You know how she is, always full of energy.”

“Can’t argue with that.” Applejack chuckled. “Well then, Ah’ll see you there then. Gonna head out in a couple minutes mahself, was just about to hand over the stall to Big Mac when Ah saw you.”

“Oh yes, I should be on my way as well. I was hoping to do a little detour by the park with her before we head to Pinkie’s. I’ll meet you there, then.” Twilight tugged lightly on the leash. “Come along now, Dashie, you’ll see her again soon.”

Dashie shivered, still in a bit of a haze as she clumsily moved past Applejack and followed Twilight. As they kept walking though, she slowly calmed down, getting more and more confident as they passed dozens of ponies without a single comment that wasn’t just remarking on how cute or well behaved she was.

By the time they reached the park, Dashie was going so far as to run ahead of Twilight for short stretches, sitting down and wagging her tail as she waited for her and drawing chuckles from the surrounding ponies. She even posed for some of them, accepting pets and compliments, although thankfully Twilight saved her from one pony’s well-meaning offer of dog treats by citing Pinkie’s upcoming party.

They’d been out for close to an hour by the time they reached Sugarcube Corner, and from the sounds coming out the door, the rest of their friends had already arrived. Dashie happily pulled Twilight along, waiting impatiently for Twilight to open the door for her before pouncing into the bakery and almost tackling Pinkie Pie in her excitement. She happily nuzzled her head into Applejack’s shoulder, accepted pets from Pinkie Pie and showed off her collar to Rarity while Fluttershy cooed over her.

Twilight let the scene play out for a while before clearing her throat and giving the leash a light tug. “Pinkie? Do you mind if we use your room for a few minutes? I wanted to give Dashie here a quick brush-over before the party so the Cakes don’t have to worry about her shedding inside the store. I have all her grooming stuff with me.” She lifted up the bag she’d been carrying around on their walk.

“Oh! Sure thing, Twilight! Don’t worry about my room, a bit of Dashie fur is nothing compared to the hairs I lose in there.” Pinkie giggled, waving her off as Twilight led Dashie over to the stairs and took her up to Pinkie’s room.

Rainbow blinked as Twilight unhooked the muzzle and started opening up the socks over her arms and legs as well. “ ‘umfin homg?” She yawned and worked her jaw for a moment before stretching out her arms and legs. “Not that I mind the opportunity to stretch myself out, either way.”

“Well, it’s probably a good idea to let you stretch either way. You haven’t been in those things for this long since the time I accidentally fell asleep on you.” Twilight giggled. “And back then you weren’t moving around much.”

“Oof, yeah. I probably could’ve kept going, but better safe than sorry.” Rainbow stretched her arms high over her head, shifting back and forth to stretch her legs before giving Twilight a suspicious look. “But that’s not all, is it? You’ve got that smile on your face again.”

“Weeeeeell… I might have packed a thing or two for the party…” Twilight grinned and opened up the bag, pulling out a very familiar large bundle and a small enchanted air pump.

Rainbow squeaked, face turning bright red in an instant. “Y-you can’t be serious! There’s absolutely no way…”

“I maaaaay have made a few small adjustments. So, what do you say? Do you want to give it a test?” Twilight waved the bundle before her smile softened slightly. “I wouldn’t blame you if you decide to just wear the muzzle and paws for the rest of the evening, you know? Or just go out as yourself, even. I did pack some clothes for an emergency.”

Rainbow swallowed, slowly staring between Twilight’s face and the bundle of shiny fabric she was holding.

~~~~~

“There you are, Twilight. We were starting to get worried that you triggered some sort of trap in Pinkie’s room.” Rarity giggled softly at her own joke.

“Oh, I’m sorry. It’s just that I kind of brought another friend along and needed to get her ready for the party.” Twilight grinned and turned her head to look up the stairs, horn glowing as she started floating said friend down the stairs.

“O-oh my…”

“Well gosh darn, ya brought Rainbow Dash along? Ah didn’t know it was that kind of party!”

“Neither did I, darling.” Rarity leaned forward and licked her lips. “Although that’s not to say that I won’t take her back up to Pinkie’s room myself for a bit later. And here we were wondering why you took so long upstairs, Twilight you scamp~”

Twilight choked and sputtered at the insinuation, blushing as her friends all giggled at her. Instead she focused on bringing Rainbow the rest of the way down the stairs, giving her another good look as she floated past.

Rainbow Dash was clad head to toe in shiny blue, semi-transparent rubber. While her body and head were covered skintight, the rainbow latex of her mane and tail were inflatable to give them a nice cartoony shape while keeping her actual mane and tail some breathing room that would keep them from getting too tangled and sweaty. Similarly, her arms and legs were inflated an inch or two off her skin, put under enough air pressure to keep them straight and stiff and ending in a quartet of big inflatable rubber hooves. Most importantly though was the pair of cutie marks printed onto the flanks of her skintight latex suit right over her actual cutie marks, showing a rounded pony silhouette in a rather recognisable pose with the only details being its two most recognizable features, one on the face and one between its legs.

She carefully set Rainbow down on her hind hooves and giggled as her friend flailed for balance for a moment before taking a few wobbling steps forward. That was as far as Rainbow got before Pinkie Pie appeared in front of her and pulled her into a big hug. The ~~pegasus~~ toy moaned helplessly through the stiff rubber gag that was once more holding her mouth open, squirming as Pinkie started rubbing and toying with the big rubber dildo between her legs… the opposite end of which was pushed nice and deep up Rainbow’s pussy inside the suit, enchanted to transmit every last sensation from its other half.

Twilight blushed and giggled before looking at her other friends, slightly nervous. “I hope I didn’t overstep any boundaries. I know it wasn’t supposed to be this kind of party originally.”

“Nonsense, darling. A friend is a friend, sex toy or not, we’d hardly be good friends if we kicked dear Rainbow out of a party.” Rarity tossed her mane. “A lady like myself doesn’t kiss and run like that.”

“Exactly. Ain’t nothin’ wrong with a good roll in the hay, and Rainbow here is prolly the best roll anypony could ask for.”

Fluttershy shuffled her feet with a soft blush. “I, uhm, I don’t mind. I like Rainbow Dash… a lot.”

Rainbow squeaked and blushed again, squirming and moaning as her friends started to shamelessly talk about all the things they’d do with her before the end of the night. A shudder ran up her spine as Twilight leaned in while the rest of their friends were distracted with their increasingly animated discussion (and not a small amount of charades from Pinkie Pie) to whisper in her ear.

“Don’t worry, this suit holds much more magic than those stickers. I can easily leave you with one of our friends and pick you up in the morning~”

Twilight winked and gave Rainbow a light teasing pat on the cheek before stepping away to join the rest of their friends, blushing and giggling as behind her Rainbow bucked her hips with a loud moan and came for the first but certainly not last time of the day.

Author's Note

You all thought you knew what you'd get from today's prompt, didn't you? Someone brainwashed into a pet, or maybe a fancy subversive comedy piece about hypnotizing someone into a dom. NOPE! Consensual wholesome petplay time! We're hypnotizing literally everyone else instead!