Femme Fatale Acompli

by SirSirloin

Rating: mature
Tags: Crossover, Alternate Universe, Anthro, My Little Pony: Friendship is Magic, Fetish, Rainbow Dash, Rarity, Sonic the Hedgehog
Length: 4378

The potential setbacks of making Rainbow Dash, A) competent, B) utterly amoral.

Rarity and Rouge think they're the smartest smugglers on Mobius. After all, who else would think of hypnotising Rainbow Dash into their perfect third partner, combining their tastes and skills with Dash's?

However, the smartest anybody in the multiverse might have considered the potential setbacks of making Rainbow Dash, A) competent, B) utterly amoral.

Soon Dash's prudish partners won't be thinking anything, except what she wants them to...

Crossover fic for Superfun. Hypnosis, emphasis on personality change, and the mental image of three hotties in SEGA's most iconic outfit.

Cover art by Lettuce.

Rouge Dash custom commission info with Ts and Cs here.

Published 2023-11-14 18:00:00 UTC
Last updated 2023-11-14 18:00:00 UTC

Femme Fatale Acompli

All eyes on her. Just as they should be!

Rainbow Dash resisted the temptation to put a gloved hand on one of her swaying hips or to bat her lashes at a few of the more attractive guests of this hotel who were staring at her. Who could blame them? Her face, her trademark hair, her eyes, and that was before you got to her outfit! Well, her partner’s outfit and she was wearing a sumptuous fur coat over it, but semantics. That makeover and the lifestyle that had come with it had been the best thing to ever happen to Rainbow. She owed Rarity and Rouge a lot for inducting her into their little gang! And she had a hunch she’d be collecting on it tonight.

“Bonjour, mes chéris!” she cooed, gliding perfectly into their private suite. She shrugged effortlessly out of her coat, using her wings to drape it over one of the plush chairs and revealing her athletic body clad nice and tight in a perfect copy of Rouge the Bat’s latex catsuit.

The bat herself and Rarity, who was wearing a stylish but, Dash thought, rather conservative purple business suit with some black knee-high boots and black gloves, glared at her from their chairs.

“Awww,” Dash snickered, “you two babes are waaaay too hot to look so cold! Whaddaya say we order up some drinks and you can tell ol’ Dash what’s upset you? And then she can make it all better!~”

“I’ll tell you what’s ‘upset’ me, you little ingrate,” Rouge snarled, taking a step forward.

“Rouge, darling,” Rarity sighed, putting out a hand to stop the bat. “First thing first. Did you at least acquire the target?”

“But of course!” Dash mock-pouted and retrieved a necklace of precious stones from a secret pocket in the pink cuff of one of her gloves. “You know I could never disappoint the two thieves I love the most in the world! Well, apart from me, obviously.”

“Obviously,” Rouge muttered, taking the necklace from her. The bat’s expression softened from a scowl into an almost glaze eyed look of rapture as she held the necklace up to the light. “Oh god, it’s even better up close. We can make millions selling off the lesser stones and the rest’ll look so perfect in our collection forever…”

“Or we could make something truly perfect and wear them ourselves,” Dash purred, in a tone of voice almost identical to Rouge’s, much as her French accent was to Rarity’s own.

“That’s why we wanted to have this little meeting, darling,” the Unicorn said sternly. “You know we don’t wear the goods in public. Not unless we’re sure the heat’s completely died down.”

“Counterpoint, we’re supposed to be the world’s greatest thieves,” Dash shot back. She blinked as Rouge slammed a glove into the headrest of her seat, right next to her ear, and leaned in close. Normally having the bat’s gorgeous white furred face (and the rest of her!) so close was a source of unbelievable, smoking hot awesomeness for Dash. Not this time. Not with the way Rouge looked now.

“And do you really think,” Rouge snarled, close enough for Dash to see how sharp her fangs were, “the world’s greatest thieves could call themselves that if they wound up in the slammer? For something as fucking stupid as wearing the merchandise in public, right after they boosted it?!”

Dash made a big show of shuddering. Rouge smirked to herself right up until she saw the Pegasus’ eyes and realised it was sensual, not from being intimidated. “Mmmm, I just loooove when you talk all criminal-like, Rouge.~”

“Oh, for fuck’s sake,” the bat sighed, spinning on her heel and passing Rarity the necklace as she marched over to a corner of the room. “Here Rarity, you hold this, I’m so pissed off I might break it. That’d be the last thing we’d need after this disaster.”

“Uh, excuse me?” It was Dash’s turn to scowl now. “What disaster? I just pulled off the job of the century! For the tenth time in a row! In, out, awesomeness all about!”

With a blasé expression, Rarity used her telekinesis to work the hotel suite’s TV. It turned on to one of the news channels. An international one. The footage showed the skyline of Solana, the gang’s current location, at night lit by fireworks.

“–lighting up the historical district for blocks,” the voiceover was saying, “eliciting cheers from onlookers despite a district long tailback, caused when startled motorists collided. Thankfully, only a few minor injuries have been reported and even those victims agree that the sudden display has put them in an even more festive mood.”

“See?” Dash leered. “Those fireworks were the best cover a girl could ask for!”

“The fireworks,” Rouge snarled, “weren’t supposed to go off until Saturday.”

“It is the festival of fire,” Dash mock-chided, putting one hand on her shiny latex clad hip and wagging a gloved finger.

“It’s the week before!” both her partners snapped in sync. Although right now, Dash thought bitterly, they sounded more like parents. Gave her all the orders and then yelled at her for following them…

Rarity turned the sound down and pointed at the footage of a rainbow streak weaving between the bursting fireworks. “That’s you, isn’t it? You set the district’s stash off early so you could fly out, instead of using the route we told you to!”

“Well duh,” Dash retorted. “You wanted me to use the sewers!”

“That was an example!” Rouge groaned, dragging her own gloved hands down her face. “The sewers or the subway tunnels or the alleyways, we said.”

Dash balanced perfectly on the heels of her pink and white custom leather boots to simultaneously gesture at the catsuit hugging her body and her perfectly formed cyan shoulders, her work-of-art rainbow mane cascading past them. “Guys. Darlings. Babes. Look at me. Does somepony who looks like me use gross places like those to make their mind-blowing getaways?!”

“The point is that nopony is supposed to ever see you!” Rarity snapped. “Bad enough you quit the Wonderbolts so publicly, all it will take is one of them getting suspicious about this footage and trying to keep track of your movements–”

“And what?” Dash scoffed. “We’re the world’s three greatest thieves! Even if those lameasses figure out I did it they’ll still have to prove it! C’mon, our looks and brains, they’ll never be able to hold us! Not unless it’s real tight and real hot, anyway.~”

“I didn’t teach you to flirt your way out of trouble just so you could get into it,” Rouge said, glaring out the window with her arms crossed.

“This should’ve been a simple, quiet in-and-out job,” Rarity agreed, brandishing the necklace.

“And using loud and stylish got me in-and-out even easier,” Dash shot back, walking up to her so they could glare at each other. “What’s your point?”

“The point is that this keeps happening!” Rarity snapped. “You keep pulling these stunts, using a sledgehammer when a scalpel is what’s called for! We know you can do better, like we trained you. Every job you worked with Rouge went smoother than the silk of my favourite stockings.”

“Yeah, when I was in basic-ass tutorial mode,” Dash muttered, rolling her eyes. “You guys trained me to be a perfect fusion of me and Rouge, and I love you for it, but I don’t have to take this. You made me part of this team and then you let me off the leash to do things my way.”

“And now we wonder if that was a mistake,” Rouge sighed. She walked over and gently caressed Dash’s face. The Pegasus let her, watching the bat’s eyes intently. “I should’ve figured combining our egos would result in something spectacular.”

“Damn right,” Dash smirked.

“But this is the thieving business, Dashie,” Rouge corrected, sounding gentler than she had all night. “Millions of dollars for a million dangers. And we can’t risk you turning into one of those dangers.”

“So we’re going to have to consider giving you another makeover,” Rarity said. She smiled encouragingly. “That wouldn’t be so bad, would it, darling? You enjoyed the last one so much.”

“Heh, yeah, I did,” Dash chuckled softly. She held up the necklace she’d stolen tonight, mildly surprising the other two because they hadn’t seen or heard her take it from Rarity, but then again, they had trained her in the art of lifting such things. “Being made into a whole new person, a mix of myself and you two…it’s the most intimate thing that’s happened to me, like, ever. And it was so cool the way ya did it! Using a piece of jewellery, just like this one! Holding it up like this, showing me the light of the starts dance on it, just like this. How it starts to make you feel so safe and relaxed, just like this. How it makes my voice the most powerful thing in your universe, just like this. How soon you are totally, utterly under my control…just…like…this.”

Neither of her partners said anything. They were too busy staring into the light shimmering on the facets of the treasure in her hand. And listening to the sound of her voice, of course.

“Heh,” Dash smirked, gently holding the necklace from side to side, up and down, enjoying the sight of the two beauties’ expressionless faces and dulled eyes turning to keep track of it, “yeah, just like that. Just like how you two led me into the back of Rarity’s boutique and made me ever sexier than I already was. Here’s the thing, though. You really don’t get to give me an appreciation for the finer things in life and then tell me how to enjoy them. Are we thieves, or aren’t we? Say ‘Yes, Rainbow.’”

“Yes, Rainbow…” Rarity and Rouge replied, voices devoid of emotion, their eyelids drooping.

“So we should act like it, shouldn’t we?”

“Yes, Rainbow…”

“We should enjoy it, shouldn’t we?”

“Yes, Rainbow…”

“But, since I’m the most badass, I should be in charge, shouldn’t I?~”

No response.

“Ahem!” Dash snapped, petulantly stomping one of her boots heels as she held the necklace even closer to their mesmerised faces. A hundred copies of Rouge and Rarity’s lifeless faces stared back them through the rainbow sheen of its facets.

“Yes, Rainbow…”

“Yes what?”

“You should be in charge, Rainbow…”

“That’s my girls,” Dash smirked. “And you are my girls now. My girls are gonna be whatever I want, aren’t you?”

“Yes, Rainbow…”

“Well, there’s a certain pink hedgehog I’ve always thought could teach you gals a thing or two, soooo…”

***

“This way, my darling Dashie!” Rarity cooed, her high heels clicking off the asphalt as she skipped down the sidewalk, grinning and clutching the sleeve of her favourite mare’s fur coat.

“Alright, alright,” Dash grinned, sunlight from the bright new day making her sunglasses almost as shiny as their latex, “I can’t believe you’re gonna make me say this, but slow down!”

“Awww, but Dashie!” Rarity whined in her new, strangely high pitched and giddy voice. “There’s only twenty four hours in a day! That’s almost no time at all to let my one true love know how I really feel about her!”

“Well, babe, you did just use the term one true love,” Dash smirked, wrapping the arm Rarity was holding around her waist. Rarity’s suddenly blushing face was reflected in her shades, and it felt like her own heart was going to beat its way out through her breastplate at the delicious sounds of the fashionista’s girly new giggle.

That giggle was drawing a lot of attention from pedestrians, as was the sight of Rarity clad in a full-on Rouge outfit. At least Dash was wearing her fur coat over her own…and loving the sight of the outfit on Rarity’s body, not just because it looked so damn good but because the irony of little miss ‘Nopony is supposed to see you’ making people wonder if she was on drugs, a prostitute or a prostitute on drugs was, like, poetry or something.

“Oh Dashie, you’re sooooo smart!” Rarity babbled, wrapping her gloved arms around Dash’s shoulders. She let out a cartoonish ‘Eep!’ as Dash confidently swept her up, carrying her in both arms like she weighed nothing. Rarity sighed happily and lent in to nuzzle her obsession’s neck. “And strong and funny and beautiful and powerful and perfect and a whole lotta other stuff…”

One of the things Dash most enjoyed about her own transformation was her improved vocabulary, based on Rarity’s own, but she was equally enjoying the slight reduction of her partner’s. A small price to pay to keep Rarity and Rouge in their places. Rarity was slightly less articulate and a lot gigglier because that’s what she thought of when someone said the name “Amy Rose”. Rouge was even more contemptuous of the hedgehog, but then familiarity was supposed to breed that. It had come in handy last night, when Dash had ordered her hypnotised subjects to picture and describe their mental images of Amy. With the added order that the more they thought about her, the more they’d become like her.

And the result in Rarity’s case was this. A giggling, fawning, lovestruck sugar momma. Or she would be once they reached the department store Rarity had begged and pleaded to let Dash take her to.

Once there, Dash had the most fun she’d had since she’d woken up with Rarity’s taste and Rouge’s skills (and both their egos), watching as Rarity tried to explain to the confused assistance how it was vital they pick just the right outfit to be worthy of her Dashie!

“I mean, you can see it, can’t you? The way the sun dances off her…well, we’re indoors now, but even in this mediocre lighting can you not see how Dashie’s perfect hair glows like a halo, illustrating what an amazing living angel she is? Oooh, she could wear a garbage bag and make it look perfect!~ So yes, could you be a total lamb and fetch us an ensemble that captures all of that? Oh, that’s okay, we’ll just browse then. Any excuse to spend more time with my Dashie!”

And Dash enjoyed spending so much time with her Rarity, listening to the non-stop praise coming out of her mouth in her humiliating new voice, watching the way other customers stared at Rarity’s body in Rouge’s suit with the mare herself oblivious to the lust, the soft little sound that came out of Rarity whenever Dash praised or touched her.

Even shopping was a pleasure, now that Rarity’s brainwashing had expanded Dash’s horizons. True, in the past Dash would’ve found looking for anything other than a jacket, jeans or skirt a slow-moving pain in the ass, but now that she had the combined fashion knowledge of Rarity and Rouge she found putting together the right look almost as much fun as lock picking, with the added bonus this was all about making her look even hotter than she already did! And the best part? It was just one more thing at Rarity’s expense, sweet payback for all the times her would-be mentor had bitched about Dash running up Tirek sized expense accounts!

It was also just one more way to twist Rarity around her little finger, once they were in the changing rooms. Dash of course insisted on her sweet fashion consultant following her inside, pretending with sadistic delight not to notice the way Rarity reddened, moaned and bit her lip at the sight of Dash slipping out of her suit and into outfit after outfit.

“What about this one?”

“P-perfect Dashie, just perfect!”

“You sure, babe?”

“As sure as the sun’s gonna rise tomorrow! Those rags were nothing until my darling put them on!”

“Heh, it’s just, y’know, you said that about all the other fits too.~”

“D-did I? Oh. Heh, well! That’s just ‘cause it’s true! Oh Dashie, I love you, promise me you’ll never stop being this perfect!”

“Anything for you, babe. Now, what about this one, with the garter belt?~” [Thud] “Rarity? Rarity?!”

Alright, so her new thralls were only flesh and blood, and Rarity has sprayed an impressive amount from her nose all over the changing room wall from Dash’s smoking hot antics, but what the hell, Dash had been planning to burn through Rarity’s credit card anyway. Once she’d been revived, had some water and cleaned her nose, the Unicorn was still her happy, dippy new self, cheerfully asking the frantic store clerks if they had anything in magenta, ‘cause that’d totally bring out her Dashie’s eyes!~

“Five thousand, huh?” Dash smirked when they finally came to the check out. “Oh dear, I seem to have left my wallet with my other catsuit, Rarity, I hate to ask, but could you…?”

“Of course not Dashie, you know I’d cut my hands off if you asked me to! Everything I have is yours, I’m only sorry these tawdry pieces of plastic are among the best of my pathetic offerings to your perfection!”

The cat girl at the register stared as Dash patted the happily paying Rarity on the head, wondering if she was watching some kind of dom-sub relationship. Which she was.

Not wanting the fun to be over, Dash staged a little drama as their hired car arrived to take their shopping…or more accurately, the somewhat bemused driver was told to stay at the wheel while Dash ordered the obliging Rarity to load every single bag into the limo, a process that involved the prim and proper mare showing her latex clad ass to every single passer-by as she repeatedly bent over to attend to her task. She even did it with her tail hitched high when Dash ordered her too, all the better to expose her round, shiny black cheeks.

Dash made a show of patting herself down once Rarity was finished, then struck a dramatic pose that made her whole catsuit squeak. “Oh nooooo! My wallet!” She pointed at a finger at a nearby traffic warden. “Rarity, that awful, awful man stole my wallet!”

Rarity gasped, then spun on her high heels hard and fast enough to send up sparks, her face so furiously reddening that the only white left was her bared, snarling teeth. “How DARE you!” she shrieked.

To the astonishment and bewilderment of all onlookers, she threw up her hands, her horn glowing as it conjured a massive, jewel encrusted piko piko hammer, catching it and screaming as she swung it back and charged towards the poor public servant.

“No one steals from my sweet Dashie-Washie!” Rarity screamed. “You hear me?! NO ONE!!!”

Dash grinned, folding her arms and leaning casually against the limo, turning her head to follow Rarity chasing the cop back and forth, swinging her hammer so much she demolished several streetlights and even a fire hydrant, spraying water straight up into the air, which made the Pegasus finally crack and burst into uncontrollable laughter.

Finally, the traffic warden tripped while trying to duck one of Rarity’s wild swings, sprawling on the unforgiving asphalt. He started up in terror as the beautiful, latex clad lunatic loomed over him, blocking out the sun as she raised her hammer above her head for the ultimate swing.

And then an angel (or at least the shapely backside of something with wings) dropped down in front of him. “Wait!” Dash cooed, holding up a black leather wallet with a pink winged-heart logo. “Silly me, it was in my pocket all along!”

“Oh, well, that’s alright then,” the instantly bubbly Rarity chirruped, banishing her hammer back to whatever hell she’d summoned it from. She giggled and pirouetted on one leg, clapping her gloved hands in celebration.

Dash wrapped a proprietorial arm around her, guiding her to the limo, where she insisted her darling enter before she did…so she could make sure an entire street of still staring strangers could witness her deliver a proprietorial slap to Rarity’s one in a million ass. The only thing better than watching the way sunlight danced of Rarity’s jiggling latex cheeks was the feel of how round and perfect they were against her hand.

“Eeeek!” Rarity squealed, her tone almost hitting a pitch identical to the squeaking of her catsuit. It became a loving giggle just as instantly. “Oh, Dashie…~”

***

Dash didn’t have that many ideas for a perfect way to wrap up her first day of fun in the gang’s new hierarchy. She was kind of hoping the main one would be waiting for her when she returned to the hotel, but if not, well, she could have a lot of fun improvising ways to pass the time until it was.

For now, she enjoyed the sight of Rarity skipping merrily through the hotel as she carried two large bag full of Dash’s shopping, still in full Rouge costume, drawing even more looks from the guests as she hummed the ‘sweet-sweet-you’re-so-sweet’ segment of Sweet Passion. Dash smirked to herself, revelling in the combination of Rarity’s new outfit on her body and her new personality. Her dignified partner in crime was gone and Dash wasn’t going to miss the original Rarity if her custom version was going to look simultaneously innocent and fuckable like this.

And as if the make out session in the elevator with the new Rarity wasn’t enough, Dash just kept on winning once they reached their suite; the new Rouge was waiting for her.

“Dashie!” Rouge cooed, flapping over on her wings and throwing her arms around her. “You’re back, you’re back, you’re back!”

“Happy to see me, hmm?” Dash smirked.

“Oh Dashie, you don’t know how glad! This city is sooooo romantic and everything but if I thought anything had happened to you here, I’d burn it to the fucking ground!”

“Well good thing I’m too badass for anything like that to happen,” Dash soothed, gently boopy her former superior’s cute little bat nose with a gloved finger, “so you, me, and Rarity can just focus on being hot together, right?”

“Yu-huh!” Rouge giggled, her wings fluttering all lovely dovey and giving Dash the perfect rush. Those things were Rouge’s pride and joy, and just like Rarity she was reducing everything about herself to this lovestruck caricature.

“So did you bring me anything special?” Dash asked innocently, as if she hadn’t been aware of the glistening radiance clutched in the bat’s left hand the entire hug.

“Oh, duh!” Rouge lightly smacked her forehead with her free hand then cupped it with the other so she could hold out one of the royal Soliana beryl coronets, from some distant marriage Dash would never care about, like an offering. “And I did that other thing you asked too, ‘cause my entire reason for being alive is making you happy!”

Dash raised an eyebrow. She knew she was essentially perfect as well as her new thralls did, but that order had been as much a test of her skills as a hypnotist as of Rouge’s new loyalty. “So you did this little job in broad daylight not caring if anyone saw you?”

“Yuh-huh!” Rouge giggled again. “You were right, obviously, like always, if were the best thieves in the whole world then what difference does it make what time of day it is? My and Rarity’s love for you burns 100%, 24/7!”

“Here, here!” Rarity agreed, catching Dash off guard with a sudden but not unwelcome hug. Dash got some style points back as Rouge jumped into the embrace by freeing her wings and wrapping them tight around her girls.

“Awww, you two!” she chuckled. “So you don’t care that you’ve both been seen, in uniform and committing pretty public felonies, essentially burning most of the bridges that let you both get away with the subtle sides of our operations?”

“Yep!” both minions chorused.

“Good, ’cause I’ve got plans for our little group,” Dash smirked, admiring her reflection in a handy mirror. Herself, badass as she was beautiful, sophisticated as she was sociopathic, and divine as she was devilish.

So what if her fun permanently screwed Rarity, Rouge and her former self’s oh-so-useful heroic reputations? They’d been good covers for getting into whichever country their latest target was staying in at the time but who Dash was now–and forever–had no intention of hiding anything about herself from the world. It was going to love her, its greatest thief, and if not, she’d make damn sure it hated her. She would never allow it to ignore her or forget here.

Speaking of love, though…

Dash sighed and broke the hug, strutting over to one of the suite’s plush armchairs and flopping down. Instantly her two white coated beauties were swooning all over her, cooing and pleading her to tell them what was wrong and what they could do to make it all better.

“Oh, just tired, my babes,” Dash sighed, putting her head back dramatically in a perfect imitation of Rarity’s old self. “I’ve just done so much walking today!” Yeah, she thought, smirking like Rouge’s old self, all over the two of you. “I don’t suppose I could convince the pair of you to look after my poor hooves?”

“Of course, Dashie!” Rarity bleated, her suit squeaking as she dropped to her knees and hefted up Dash’s left leg. “Your precious hoofy-woofies are our favourite-est part of you!”

“Along with, y’know, your wings,” Rouge agreed, nodding vigorously as she caressed the thigh of Dash’s right leg, stopping just above the cuff of her boot, “and your hair, and your voice, and your lips, and your neck, and your eyes that’re more precious than any gem in our collection!”

“Awww, you two spoil me so!” Dash giggled. Then leered. “Keep it up.”

“Yes, Dashie!” her minions chorused.

“But first…”

“Yes, Dashie?” Again in perfect sync.

“Kiss my boots.”

“Yes, Dashie!”

“And then lick ’em ’til they’re sparkling like the latex around my perfect ass.”

“Yes, Dashie…” This time breathy and muffled by the proximity of two of Mobius’ most cunning divas now worshiping the boots of the thief queen monster they’d created.

END…?