4chan rara story

You give a furtive glance at the clocktower just beyond town square, wondering if you're too early.  No sooner do you think that when the purple barn style doors of Carousel Boutique throw themselves open.
"Daaaaaarling!  You made it!" says Rarity, the fashionista's voice drifting outside long before she makes her way to the doorway.  "And so punctual, as well!" She was in the middle of working, a pair of red catseye glasses perched on her snout and a pencil tucked between one of her ears and her curly, purple mane.  You flush a little at the sight of her.  "Well, don't just stand there, come in, dear!  I've been looking forward to this all day!" she says, shutting the door behind you with her unikinesis as she leads you across the neat and austere showroom towards the back.  "Honestly, you don't know what it means to me that you said you'd do it.  I was starting to think I would have to spoil the secret before I could find somepony who wasn't too busy to help me, no questions asked!  I must say, you've certainly saved my skin."  You remember it fondly; she gave you a kiss on the cheek when you told her you would.  "And I also thought this would give us some time to get to know one another.  I've barely seen you since you moved into town, and you've hardly said a word!" she says.  You clear your throat softly and breathe in, about to say something, when a white, finely-hooficured hoof jabs itself in front of your face, silencing you.  "Now, I'm sure you've been wondering what this big secret of mine is!" she says, biting her lip and giggling excitedly.  "Well, voici!" Rarity says, throwing open the door.  Sheets of fabric lay draped across the floor and furnishings of the untidy back room, and several design sheets of what look like giant, rotund fish are fixed all over the walls.  She shuts the door behind you softly.  "Skywhales!" she says, practically shouting with excitement.  You give her an eager smile, feigning understanding.  "After two hundred years, some pegasi have found the herd of skywhales and they're coming back to Equestria!  There'll be a royal ceremony to commemorate the occasion, and who do you think was asked to design their ceremonial clothing?" she says, sitting among all the mess with a tiny, smug smirk and a hoof proudly on her chest, "Hm!  It's me." she says, simply, bouncing her mane on her hoof.  "Oh, isn't it just grand?" she says, taking the whole room in.  You look around at all the colored fabric, not sure what she needs you for.  She offers a hoof to you and you take it.  "However, if any of these outfits are to turn out right, I shall need a model.  And you, lucky new pony, get to try them all on!"  She leads you to the center of the circular room.  You're a little confused as to how you'll be modelling clothes intended for whales, but you don't know much about fashion, so you assume she knows what she's doing.  "Right!  Let's crack right on with it.  Here, give this a try." she says, her horn lighting up with magic.  You look up just in time to see what looks like a big blanket surround you on all sides.  It warps and bends in Rarity's magic, and you flinch away from it as it curls around your body.  The sheer, light fabric pours over your body and flops on the floor around you.  You open one eye, then the other.  The thing is spread in a huge, limp circle around you.  You experimentally lift up this leg and that, looking around at the light, slightly stretchy fabric in confusion.  "Of course, you're not quite the right size for it.  Or the right shape." you can't help but smile a little at the bizarre situation she's put you in, and you look up at her, standing by her bureau.  "Well, not yet, anyway." she says, her horn glowing with magic, and seemingly out of nowhere, a fireplace bellows floats over to her, surrounded by her magic, and demonstratively pumps itself open and closed a couple times.  Your smile immediately falls.  "I was told that they use lighter-than air gas to keep themselves afloat.  Now, just a few puffs of this and you'll be the perfect stand-in for me!  It's not lighter-than-air, but it'll have to do." she says, walking towards you.  You back away from her, nervously, but your hooves tread on the skywhale outfit you're wearing, slipping and stretching it and losing your balance, landing on your haunches.  "Oh, don't give me that face, darling!" she says, walking to within hoof's reach of you, the bellows hovering menacingly next to her, "I told you I couldn't find anypony else who would do it no questions asked!" she says, tipping the bellows towards you.  You recoil away from it.  "No, please don't shy away now!" she says in a low, moaning voice.  All the sudden, her big blue eyes get all misty.  She throws herself to your forehooves, begging.  "Pleeeeease, please, please, please!  This means so much to me and I don't know what I would have done if you hadn't helped me!" she says, looking up at you with big, tearful, doe eyes.  Your heart is sinking.  "I would be eternally grateful!" she says, and all the sudden the memory of her kissing you on the cheek springs back to the forefront of your mind.  You look away, giving a frustrated sigh.  You can't believe you're actually about to do this.  You offer her a hoof, which she looks at in surprise.  Sniffling, she takes it, and you help her back up to her hooves.  "Does...does this mean...?" she asks, hopefully.  You give her a friendly look and a curt nod.  Her face and eyes immediately light up with joy and she squees with excitement, wrapping you in a tight hug and giving you another kiss on the cheek.  Your cheeks turn a piping hot red with blush and a dumb, satisfied smile spreads across your face.  "I knew you would come around eventually." she says.  You slowly nod in agreement.  "Now, open up for me!" she says, the bellows angling themselves towards your face.  You get to all fours and open your mouth.  The metal nozzle of the bellows quickly and roughly shoves itself into your mouth, knocking you back a little and shaking you back to your senses.  Blinking in surprise, you look at the big contraption sticking out of your mouth, suspended in the place by Rarity's magic.  The two halves of it spread apart, the bellows taking a big intake of air.  You're starting to regret your decision a little.  And just like that, the halves press together, pumping all of its air into your mouth.  Your eyes go wide as your cheeks poof out and your belly fills with air.  And before you can recover, it opens back up and pumps again.  You watch the bellows uneasily as it pumps and pumps and pumps, your cheeks puffing up rhythmically and your belly strains and expands, pulsing out and out with the rhythm of the pumping.  You mumble behind the nozzle, your flanks puffing outwards as your whole body grows rounder and rounder.  You glance to your side and see Rarity biting her lip and grinning, watching your expanding body intently, her horn glowing with magic.  You can see the edges of the round costume, draped across the floor, slowly inching and shrinking towards you in rhythm with the pumps.  You shut your eyes, trying to keep cool as you feel your own midsection against your legs, feel your sides wrinkle and rub together, hear your own hide squeak like a balloon, feel yourself plump and swell up and out, growing bigger and rounder by the second.  Your hooves scoot further and further apart in rhythm with the pumps, sliding on the loose costume to make room for your ballooning body.  They slide further and further outward, and you find it harder and harder to remain on all fours.  With a pump, they all slip and you gasp, sucking down more air from bellows, as your fall is suddenly and abruptly broken by your now massive belly.  You look down, blushing, as you bounce in place, your increasingly useless legs wiggling and your tail twitching, lightly brushing against your growing, widening rump.  Once you've settled, you notice your legs are extending outwards of their own accord.  With each pump, they stiffen outwards, and then relax.  Stiffen outwards, and relax.  Stiffen, relax.  Stiffen, relax.  Pump, pump, pump, pump- further and further outwards they extend, bloating and swelling up with more air, limiting your movement of them to small, pitiful gyrations.  As you look over the billowing, expanding mass of your body uneasily, you notice with some dread that the costume is actually starting to resemble a costume, instead of a big, loose sheet.  The sheer fabric unwrinkles and draws itself over your distended hide.  It fits you sort of like a leotard or one-piece bathing suit, your fattening bare legs sticking out of round openings in the costume.  You feebly kick your hind legs as the fabric draws tighter and tighter, stretching over your swelling body, sinking into your deepening, bulging butt crack.  Pump, pump, pump- your body has grown immensely big and spherical, slowly consuming your little inflated legs, idly wiggling your hooves as you stare transfixed at the floating, pumping bellows.  You can't tell if the creaking and groaning you're hearing is from the costume or you.  Your cheeks get bigger, bigger, your body getting fuller, and then-
She stops.  Your big, nervous eyes dart back and forth, examining the room around you, and you slowly teeter on your humongous tummy.  Your body lets out a slow, rubbery creak in the silence.
"Beautiful!" she says, pacing a slow circle around you.  "Look at that fit!" she says, and you feel a poke against your huge, inflated side that makes you flinch, although in your current state, it's more like a sudden bounce.  You look down at her nervously as she runs one of her forehooves along your costumed side.  It looks like my guesswork was right on this one!" she says.  "Marvelous..." your lips draws outwards, and you look cross-eyed at the bellows as it pulls itself out of your mouth.  You're overjoyed as the thing leaves your mouth, and a sudden jet of air shoots it out.  The blast of air fires out of your mouth and rocks you backwards a little, but before it can propel you anywhere, a finely-hooficured hoof plants itself over your mouth, trapping it shut.  Rarity looks at you with mischievous eyes.  "Ah-ah-ah!  Now, you be a good little skywhale and hold all that air in for me!" she says, wagging her other hoof at you.  You blink at her and give her a pleading look with a whimper, but she seems to be looking for something.  "Ah!  Here we go!" she says, a roll of tape floating towards her.  With some crackling and snapping, she plants two pieces of tape over your mouth in an "X" shape and lets go.  You rock uneasily, and your mouth remains shut between your two bulging, inflated cheeks.  "There you go.  No escaping for you!  You'll just have to be the best skywhale a pony could ever ask for!" she cooes, turning to walk around you the other way.  You try and you huff, your round body jiggling, but you can't blow the tape off!  "Now, I just have to take some measurements first..." she says, examining your inflated body, and then walks around you.  She walks a little too close to you, and you can feel her elegant, curly tail brush against your stretched-out, sensitive skin.  It brushes and drags ever-so-slightly across your former neck, and down across the vast expanse of your sides, sending goose-pimpling shudder across you swollen body.
The measuring tape drags and tickles across your tight hide, and she draws it tight, pressing and squishing into your bloated body.
You watch her as her horn lights up and you feel a tug on your costume.  You're surrounded by Rarity's magic, and it separates from your body.  When it finally snaps off of you, you bob on your stomach in relief at the slight decrease in pressure.  Rarity comes walking back into your view, her horn glowing and concentrating on something in the air.  You feel something else grab you from behind and your whole body contorts and jiggles from the impact and the pressure.  The first costume you tried on was way too large, and now Rarity is trying her hardest to squeeze you into the next one.  You press and bulge outwards from the pressure, grimacing and wincing as it pushes and pulls across your inflated, round hindquarters and belly.  "Come on...suck it in!" Rarity says, frustated, and with a harsh tug, squeaking against your skin, the whole thing finally slips on, conforming to your huge, round body and snapping shut behind your neck.  Rarity almost topples over from the sudden give in pressure, the pencil behind her ear falling out and pattering on the ground.  "Phew!  I think you're starting to get a little too into your role." Rarity says, panting.  You blink at her.  "Now, I just need to make some..." Rarity starts, reaching behind her ear for the pencil that fell out and feeling nothing.  "Oh, drat!" she says, spotting it on the floor.  She turns and stands over it, with her back to you, and bends over to pick it up, sticking her pert, shapely rump into the air as she does so.  Blush burns across your face as your eyes travel over her butt cheeks, waggling around in what would normally be within hoof's reach if you were normal.  She straightens back up and blows the dust off the pencil, balanced on one of her  hooves, and then levitates it back behind her ear.