A Derriere Beyond Compare

by Charyb

Rating: mature
Tags: Slice of Life
Length: 3888

Rarity asks Fluttershy to help measure her rear for a new dress. Fluttershy's always happy to help out a friend, but as Rarity (and her generous flank) grows beyond measurement, Fluttershy wonders if she's in over her head.

Rarity asks Fluttershy to help measure her rear for a new dress. Fluttershy's always happy to help out a friend, but as Rarity (and her generous flank) grows beyond measurement, Fluttershy can't help but wonder if she's in over her head.

[Macro] [Big Plushy Pony Butt]

Cover art drawn by Zajice, who makes beautiful ponies.

Published 1970-01-01 00:00:00 UTC
Last updated 2015-05-11 18:00:02 UTC

And The Ass Was Fat

Fluttershy hummed a fun little tune as she cantered down to Carousel Boutique. Today was an almost-perfect day. The sun was shining, the birds were singing — singing! — and she was going to be spending some lovely quality time with a good friend. That was about as good as it got, and it would have been a fully perfect day if only she hadn’t been cursed by Discord.

Well, no, Fluttershy didn’t know for sure if she’d been cursed or not, but she wouldn’t have been surprised if she had. She did feel bad about cancelling her tea party with him, especially after he’d thrown her a pre-party tea party in anticipation, but what else could she have done? Rarity was such a dear friend of hers, and when she’d asked Fluttershy for her help, well... How ever could she have said no?

“By slamming the door in her face,” Discord had huffed while buttering the tablecloth. “It’s quite easy, and I’m surprised you didn’t think of it sooner.”

“Absolutely not!” Fluttershy didn’t normally raise her voice with Discord, but she did sometimes need to remind him of how friends were supposed to act. “I’ve known Rarity for a very long time, and if she needs my help, then it’s my responsibility to help her. Why don’t we just have our tea party another time?”

“Well, what if I want this time? I think this time is a perfectly good time at which to grow thyme while commencing our tea party on time!”

“I’m sorry, Discord. You know I just can’t do that to Rarity.”

“Hmph!” His eyes glowed a menacing pink. “Well, then, Fluttershy! If you’re so big on Rarity, then I suppose you wouldn’t mind her being even bigger.”

To which Fluttershy had reminded him that friends didn’t curse each other. And shortly after that, she’d reminded him that friends didn’t curse at each other either.

Hopefully he’d taken both of those reminders to heart.

She knocked her ra-ta-tap knock on Rarity’s door, waiting patiently outside for her to answer. Not that she had to be patient. Rarity answered a half-minute later, looking as bright and beautiful as ever.

“Oh, Fluttershy!” she said, giving her a warm, snuggly hug. “ I’ve just been at my wits’ end all day and I’m so glad you’re here.” She paused and glanced anxiously around the door. “And you’re quite sure Discord didn’t mind?”

“Um... Not as much as he could have...” Technically true. Fluttershy gave her a reassuring smile, trying not to think too hard on Discord’s disappointment. “But don’t worry about him, Rarity. I’m here to help you right now.”

“Y-yes, of course. Silly of me to worry.” Rarity exhaled audibly and smiled back. The faintest tinges of a rosy red shaded her cheeks. “Why, um, why don’t you come inside and make yourself comfortable, dear? We can talk about what I need once we’re in the studio.”

Fluttershy nodded cheerfully, and followed as Rarity beckoned her inside. It felt good to be helping one of her friends instead of asking them for help. So good, in fact, that she could hardly stop beaming at Rarity as the two of them trotted toward the work room. Not that she’d meant to stare! She was just... No, it was... They were friends! She wasn’t trying to be rude!

No, of course not. She always had thought that Rarity was a very pretty pony. How could she not be, with all the time she spent on her appearance? The make-up, the hair-styling, the exotic floral shampoos. She caught a faint whiff of the latest scent as Rarity’s tail flicked past her nose: sweet, soothing jasmine. Beautiful.

It was maybe, possibly, hopefully just a little natural for her to stare...

“So I’ve been working on a personal project these days,” Rarity said idly. She paused to sweep the floor of Sweetie Belle’s crayons before continuing. “Spring’s just around the corner, you know, so I’ve been wanting to make something new and eye-catching for my own wear. Presentation’s important when you’re trying to catch somepony’s attention, don’t you think so, Fluttershy?”

“Mmhmm,” Fluttershy nodded, staring a little more now than was entirely polite. Her eyes widened as they settled on Rarity’s generous flank. For a moment — for just a moment, she could have sworn that Rarity had wiggled it in her own direction. But that was silly. Of course she hadn’t. She was just imagining things, like how she imagined monsters in her bed and under the closet.

“So...” Rarity wrapped her magic around a thin line of yellow tape measure and brought it over to Fluttershy. “And this is just between us, darling. I was hoping you could make some quick measurements on my hips for me? I’d do it myself, but I’ve been so fidgety lately that—”

“Of course!” Fluttershy blurted. She blushed and retreated an inch. “I mean, of course I can do that for you, Rarity. Anything for a good friend.”

“Thank you so much, Fluttershy.” Rarity let out another deep breath and smiled. “And you promise to not tell anypony about this? I hate to admit this, least of all to myself, but I’ve been getting, well... a little wider lately.”

“Lips sealed.” Fluttershy took the tape measure and nodded. “Should I start now?”

“Please, dear.” Rarity turned around and gave her hips a shake — that one had definitely been real. “Do be sure to get a thorough measurement, would you? No offense intended, but I wouldn’t want to have to trouble you for this more than once.”

“I understand,” Fluttershy said, spooling the tape measure around her hoof to get a good length. She took the brief lull to give Rarity’s rear end a good look-over — for the measurement, of course. It was a generous flank by any stretch of the imagination, and almost big enough for a bunny rabbit to use as the world’s coziest pillow.

She bit her lip as Rarity gave her flank another fidgety wiggle, the cheeks wobbling ever so slightly with the movement. There was muscle there, but not too much so. More than Fluttershy’s own and less than Rainbow Dash’s — not that she’d ever say Rainbow Dash’s rear was unattractive! But... and she’d never, ever say this either, she was secretly, really, deep-down jealous of Rarity’s curves.

There. Now she could lock those thoughts away and never think them again, because Rarity was a good friend and why would Fluttershy ever think of her like that in the first place?

“Fluttershy?” Rarity looked back. “Are you ready yet?”

“Sorry! Sorry! I’m ready now!” She pulled the tape measure out to a good length and set her hooves gently on Rarity’s supple rear. She didn’t mean to grope it or anything. It was just important that she get a good idea of where Rarity’s hips began so she could measure them thoroughly. There was some accidental rubbing and kneading of Rarity’s warm, doughy cheeks, but she was just getting a good sense for their give so she could account for it in measuring.

They were very soft, though.

“Ooh...”

Fluttershy froze as Rarity let out a quiet groan. Too far? Too far. Oh dear, oh dear. She could only hope Rarity wouldn’t hate her for this. Rarity’s flank shuddered beneath her, and a drop of something splashed against the floor. In between her panicked gasps, Fluttershy’s nose caught on a certain smell hanging in the air. Just beneath Rarity’s sweet jasmine shampoo was another scent altogether. A much thicker, muskier odor coming from Rarity herself.

“Rarity!” she gasped. “Are you...?”

“O-oh, my apologies, Fluttershy!” Rarity’s face was bright scarlet, the blush in total control. “I should have been more forthright with you. My cycle kicked in earlier than I’d expected, and I’ve been feeling a need for some... relief. I didn’t mean to—you know I wouldn’t—I just needed the measurements for this dress so I could find someone else.”

“Don’t worry, Rarity,” Fluttershy said in her most soothing tone. Rarity was clearly stressed herself, and it just wouldn’t do if both of them were panicking. “I understand perfectly.” More truthful than she might have intended. Fluttershy rubbed her thighs together absently. What if her own heat was already closing in on her? What if that was why she’d been having all of those... thoughts? Eek. “I’ll just hurry and get these measurements, and we can pretend none of this ever happened.”

“Thank you so much, dear,” Rarity said. The blush faded, but only slightly. She turned her head around and presented her rear proudly. “You take the measurements and I’ll try my best to avoid making this any more awkward.”

Fluttershy nodded and thanked her lucky stars. No more messing around for her! All she had to do now was take the measuring tape and wrap it around, so Rarity could know the size for her dress. Simple. Easy. She could do it with her eyes closed. The tape pressed slightly into Rarity’s fleshy mounds as she wrapped them with it, her eyes following the ends as they almost, just barely met.

Wait. “Oh, silly me!” Rarity’s rear had been just a little bigger than she’d expected, it seemed. Just a few inches short, but nothing too drastic. She could have estimated the rest of it easily, but Rarity wanted exact measurements and exact measurements she would get. All Fluttershy had to do was try again with a little more slack in the tape. “One more try.”

She tracked the tape again as it wrapped around the cheeks. It seemed almost to her like it was pressing deeper into the fat this time. Almost as if Rarity’s flank had grown a little bigger. A teensy bit softer. A weensy bit plusher. She shook her head. No! Silly, silly, silly. Just her imagination again. She just had to take this measurement and put all these strange and crazy thoughts out of her head.

“Five inches... six... seven...” She stopped as the measuring tape came up short again. “Huh.” She could’ve sworn she’d given it plenty of slack this time. There was no reason it should have come up short...

She’d been distracted. That must have been it. One more time. Just a few inches more slack, and she’d have it.

Rarity turned back again. “Is there a problem, Fluttershy?”

“No, no, problem,” said Fluttershy, hiding her flusteredness. “I’ll get it this time.”

“Very well!” She beamed. “I’m in your capable hooves.”

This time the measuring tape practically sank into Rarity’s flank. Her marshmallow-soft rear seemed to stretch and strain against the tape, almost as if it were pushing to be free. Fluttershy hummed nervously to herself as she made the measurement. “Seven inches... eight... nine...”

Short again.

She gulped.

“Are you sure there’s no problem?” Rarity asked, turning around in full. And that was scary. In her flusteredness, Fluttershy’d hardly noticed how much taller Rarity seemed to be now. Just a few moments ago, they’d been seeing eye to eye, but now Fluttershy’s eyes came just below Rarity’s chin.

“N-no, of course not!” she stuttered. “I’m just... Rarity, have you noticed you seem to have gotten, um... bigger?”

“Fluttershy!” Rarity gasped, scandalized. “I’d thought you of all ponies would know how rude it is to point out a lady’s weight!”

“Sorry, sorry! Not like that.” Fluttershy gulped. “Have you noticed that you seem taller?”

“Taller?” Rarity scratched her chin, looking furtively down at Fluttershy. “No more so than usual, dear. You know I’ve always been on the tall side for a unicorn.”

“O-oh. O-okay then.” There was only one explanation for all this: Discord. A prank like this was right up his alley. Quietly Fluttershy resolved to give him a very good talking-to once this was over. For now, though, she had to finish up Rarity’s measurements. What kind of friend would she be if she’d left without fulfilling her promise? Why, it’d make her no better than Discord if she did that!

“Just one more time, just one more time,” Fluttershy repeated as Rarity turned around again. This time she’d use the entire measuring tape. It’d be almost impossible for Rarity to be too big for the whole thing. The measurements would be ever so slightly less accurate, maybe, but surely Rarity wouldn’t mind if she was off by a fraction or two of an inch.

Fluttershy closed her eyes and prayed as she wrapped the tape once more around Rarity. She tried not to think about how the cheeks were big enough now for a bunny rabbit to get lost in. All she needed was a reasonable idea of the size of Rarity’s hips and she’d be done with this forever...

...She bit her lip as the measuring tape ran out before reaching the other end. Short again.

A wave of moist warmth washed over Fluttershy’s face. It felt almost like a sauna at the spa, but it smelled like something else altogether... A very familiar smell. Slowly she cracked her eyes open, only to find herself standing face-to-pussy with a massive Rarity. The glistening lips winked teasingly open and shut, revealing a light blue glow around her throbbing clit.

“Rarity!” she gasped. “Are you... m-masturbating?”

“Uungh, um... Mm?” Rarity turned back slowly, the magic glow still humming around her enormous pleasure button. “I’m sorry, what’s that, dear?”

“Are you masturbating?”

“Well, yes?” Rarity lifted an eyebrow. “You act like that’s unusual, Fluttershy. I’m a big lady and I have... mm... needs to match. You were there with me in Canterlot last March, weren’t you? Why is this a problem now?”

“Um...” Fluttershy’s gaze remained locked on Rarity’s dripping pussy, which pulsed with a near-mesmerizing rhythm. “I... no, never mind. I’m sorry.”

“Quite alright, darling.” She turned her head back again. “If you want, you can help me out. Or just finish measuring, whichever you prefer.”

“But... Oh.” She’d been about to protest that there was no way the measuring tape could wrap around Rarity’s flank now, but it seemed that had changed too. Instead of the standard yellow measuring tape Rarity usually used for customers, she was holding a silver tape — almost three times as long, and printed with the words Heavy-Duty.

There was no way now she could reach around Rarity’s flank, but Fluttershy was a pegasus and she had wings, so she flew up to get a good start. Rarity groaned audibly as Fluttershy’s hooves pressed into her pillow-sized cheeks, trying to stick the tape to a good spot. Fluttershy bit her lip and continued dutifully with the measurement. Between the thick fog of Rarity’s excitement in the air, and the bountiful softness of her flank, it was difficult to think about anything other than her own needs.

She dipped a hoof down and gave herself a quick rub. A jolt of pleasure ran through her, and the hoof came back more than a little slimy with her own fluids. That was it. That was all she’d do for now. It was embarrassing enough that Rarity was masturbating with her around... and that her pussy was roughly large enough to swallow Fluttershy’s head.

She circled around with the tape in hoof, ducking under the shadow of Rarity’s light-swallowing rear. Her head swam a little, in such close proximity to Rarity’s slobbering cave, but she pushed through and came back up to... sunlight?

They were both in a forest clearing now. Slowly she turned around and faced the rear of a four-times bigger Rarity. Even the Heavy-Duty tape in her hooves wasn’t capable of measuring that.

“Are... are you done measuring, Fluttershy?” Rarity moaned, grinding herself against a nearby tree. The glow of her horn intensified and she gave another moan, long and loud. The puddle of fluids at the tree’s base became a pond. “I want to see how big I’ll be this spring.”

“Rarity...” Fluttershy whispered. “You’re gigantic!”

“I know, darling! Isn’t it lovely?” Rarity giggled an air-buzzing giggle. “Nature’s biggest and most beautiful gem, out on display!” She giggled again, but this time it faded quickly. Instead, Rarity sighed. “I actually am quite glad you came out to see me now that I’m exiled, Fluttershy. Even after I, mm... used the Town Hall the way I did. You’re such a lovely friend, and I wanted to tell you how lucky I am to have you.”

“Oh!” Fluttershy gasped. Whatever she’d been expecting to hear from the giant Rarity, it wasn’t that. “W-well, thank you, Rarity. I’m... I’m very glad that you feel that way.”

She was very glad about that. Being a good friend was very important to her, after all. But on the other hoof, it just didn’t quite feel right to hear that from a friend the size of her own cottage. Whatever magic had caused Rarity to grow to such a size, Fluttershy could only hope it was reversible.

“Don’t... ah! Don’t mention it, dear.” Rarity let out a scream as the tree cracked under her, leaving behind a mound of bark, leaves, and warm, gooey Rarity juices. She dusted herself off and shook the debris off her rear. The mattress-sized cheeks bounced ominously. “Would you hurry with that measurement, though? I know you had plans with that Discord fellow, and I don’t want to keep you waiting out here.”

Discord! The cause of this whole mess! Fluttershy was so angry with him right now that she could just... just... just say some not very nice things! Yes, she had made plans with Rarity before checking with him first, but was that really so wrong of her?

Hardly, if this was the way he was going to act about it!

But how to measure Rarity with his curse on her? Every time she tried, Rarity would only get bigger than she could track, forcing her to measure again, and making Rarity bigger still. She couldn’t just leave Rarity to make Discord stop — that would be hopelessly rude — but how could she measure a pony whose flank only got bigger and fatter with every try?

The faintest outlines of a plan formed in Fluttershy’s mind. Every time she’d tried to get a measure on Rarity, she’d only fallen just short of the mark. Maybe that was how Discord’s curse worked: the magic kept her from making a complete and thorough measurement of Rarity’s flank. If she only measured a smaller part of it — a quarter, even — she could just multiply by four and get a number Rarity would be happy with.

Then she could go and give Discord a piece of her mind!

“Another try, Rarity,” she said gently, holding up the Heavy-Duty tape. It was nowhere near long enough to measure Rarity all the way around, but if she could just wrap a small fraction of Rarity’s marshmallow rear-fat up and measure that... It was worth a try.

“If you say so, Fluttershy.” Rarity held mostly still, though little tremors ran here and there through her fatty flank. “Do hurry up, though. I’m going to need another tree soon.”

Fluttershy gulped and very consciously avoided staring at Rarity’s steaming love-tunnel, which seemed big enough now to swallow her whole. She did her best too to ignore the huge droplets of Rarity’s juices while she set the tape up. The musk of her arousal now completely overpowered whatever sweet jasmine smell there had been, leaving the air positively reeking of Rarity and sex.

Fluttershy held her breath and prayed this last time would be the charm. She flew under Rarity’s flank, tape in hoof, brushed herself just barely against Rarity’s backside to make the final measurement, and—

“Ooh!” Rarity’s legs gave out beneath her, pinning Fluttershy beneath tons of doughy Rarity tush. Rarity’s sheer weight pinned her firmly to the ground, and would have easily been enough to crush her. But it didn’t. Instead the tons and tons of squishy fat unicorn fat didn’t so much flatten her as flatten around her, trapping her in a sauna of sweaty Rarity rear. Her hind legs, caught at the edge of the soaking furnace between Rarity's thighs, were filmed in their own special layer of marecum.

“Rarity!” she cried, her shouts muffled by the masses of jiggly flank fat. “Rarity!”

“Ah, ah!” Rarity’s own screams, a thousand times louder, replied. “Oh my stars, Fluttershy. Keep doing that!”

No help from Rarity, then. She tried to shuffle her way out, but some how the doughy mounds that encased her only seemed to get heavier and more all-encompassing with each passing second... “Oh no!” It struck her that the measuring tape must have been trapped under Rarity too, and that in some strange, hopeless way, it was still “measuring” her. Meaning there could only be more and more horny Rarity to measure.

Still, Fluttershy struggled to free herself, sliding more easily against Rarity’s sweaty flesh as the hard earth beneath her morphed into velvety cushions and Rarity's copious fluids spread further. When finally she stuck her head out into sweet, fresh air — still scrambling to stay ahead of Rarity’s evergrowing flank — her eyes shot open.

They were no longer out in the open woods so much as the exact opposite. Rarity sat now in a literal palace, big enough to contain her massive form. Light flooded in from stained glass windows, all of them cut in scenes depicting Rarity’s greatness. A chorus of ponies sang odes to Rarity in the distance. Fluttershy's heart almost stopped. In this reality, Rarity wasn’t seen as a threat or a freak, like she had been at cottage-size.

The new, mountain-sized Rarity was an Equestrian goddess.

“Are you quite done, Fluttershy?” came Rarity’s heavenly voice. She wiggled her expanding bottom, sliding Fluttershy against the cushions, and laughed. “You know I can only spare so much time for you this afternoon, even if you are the Royal Rarity Measurer.”

As if her words were the trigger for Discord’s curse, Rarity and her divine flank seemed to expand even faster. Fluttershy, just barely keeping ahead of them before, could only watch in terror as Rarity’s jiggling cheeks threatened to overtake her head and swallow her up forever.

And, in a brief moment of clarity before Rarity’s flank rolled right over her, Fluttershy realized something very important about how she’d treated her friends.

“I’m sorry, Discord!” she shouted at the top of her lungs, just as a fresh ton of Rarity fell over her. “It’s my fault for not turning Rarity down after we'd scheduled a tea party together. I shouldn’t play favorites with my friends, and it will never, ever happen again!”

And with a pop, the pressure relented.

“Fluttershy?” came Rarity’s voice, from a very normal-sized Rarity. She waved a hoof in front of her face. “Hello? Fluttershy?”

“Oh, thank goodness!” Fluttershy gasped. She paused as she realized the expression on Rarity’s face. “I mean, um... yes, I’m sorry, Rarity. What were you saying?”

“I was asking if you’d just be willing to measure my backside for me,” Rarity said, cocking her head. “If you don’t mind, of course.”

“Not at all.” Fluttershy smiled, taking the tape measure up in her hooves. “But we’ll need to hurry. I have a tea party with a friend scheduled, and I don’t want to be late.