Poni-Gurls: Muscles Are Magic

by mirandasdream

Rating: mature
Tags: Equestria Girls, Sex, Sunset Shimmer, Twilight Sparkle (EqG), Alternate Universe, Twilight Sparkle, Porn, My Little Pony: Friendship is Magic, Fetish, Rainbow Dash, Fluttershy
Length: 11322

A couple of Taur Pony Girls get up to some shenanigans.

An AU story where instead of being ponies, the girls are taurs with vast muscles and the ability to get bustier, bigger and stronger with cum.

Published 2020-01-16 23:30:01 UTC
Last updated 2020-05-01 19:58:43 UTC

A Step Across the Dimensions

“And… 400!” Shimmer panted, hanging up the dumb bell up on the rack with Twilight’s help.

“That’s incredible, Sunset Shimmer.” Twilight opened her eyes wide as she admired Shimmer flexing and checking her muscles after sitting up on the workout bench. “Your arms are just huge!”

Sunset Shimmer laughed, pulling a double curl flex, making her pecks also pump and her large breasts actually smack together. “Actually, this isn’t a tenth of how strong I am as a unicorn in the other world.”

“Wait, what?”

“Yeah!” Shimmer stood, missing entirely the twinkle in Twilight’s eyes. “Heck, the Twilight from that world is an alicorn. She would probably fill this room with muscles and tits.”

“Really?” Twilight leaned forward, her nose nearly touching Sunset’s, even as their perky breasts danced against each other like four fully inflated basketballs smacking together, each woman’s firm breasts equally unyielding.

“Uh, yeah. I mean, scale is hard to tell between the worlds because I’m so much bigger in that world too.”

“I… you… can I see?” Twilight bit her bottom lip, blushing and glancing away from the red head as Sunset Shimmer cocked an eyebrow at her friend.

“I can’t exactly just transform into a poni-gurl here. I mean, we have that hallway form when we poni up, but that’s not the same.”

“B-bigger?” Twilight’s eyes grew larger, remembering her ten-foot-tall, Amazonian body when she last poni up’d against the hydra.

“Oh, heck yeah! But how to…” Sunset Shimmer suddenly smacked her fist into her palm, the sharp smack making Twilight jump back. “The mirror! We could visit the other world and you could see for yourself!”

“Didn’t… other Twilight say something about the magical balance of the universe with us being in the same universe at the same time? And I mean, from a science standpoint, there’s the old provision about two objects occupying the same space at the same time and how that translates rather easily into-”

She was stopped as Sunset Shimmer burst out laughing. “Wow, you two really are two peas in a pod. No, you might be counterparts to each other, but you are both definitely your own persons, one of you based in magic, the other in science. I think we’ll be fine as long as we don’t make it a long-term thing.”

“Did you make it a long-term thing?” Twilight squinted as Shimmer bit her lip and looked away. “And where’s your counterpart, now that I-”

“Ok! Let’s go check out that mirror!” Sunset grabbed Twilight’s hand and the two women, both still pumped and muscled from their workout as they dashed through the school’s halls until they were outside and in front of the statue, or rather where the statue had once been. Instead a slight shimmer right at sunset let Shimmer know that the portal was open, and with no hesitation, the two well-muscled women leaped through together…

~

“Oh my… Einstein!” Twilight adjusted her glasses and stared in shock at her own breasts. Her tits had entered the Poni-gurl world ten minutes before the rest of her, or at least, that’s what it felt like. “What do I, AHHH!”

“What?” Sunset Shimmer turned and realizing her friend was used to walking on two legs and was now wind milling both her much improved musculature filled arms, the air actually swooshing around her powerful arms as she tried to catch herself and her much more top heavy, and yet also bottom heavy, body. With an intuitive movement, Sunset shimmer swung her large, orange horn around, and pointed it at her purple furred friend, catching her in an orange glow and righting Twilight’s form just before Twi toppled tits over teakettle. “Woah! You ok there, Twi-twi?”

“I uh… Sunset! Your… your mammary glands!?!”

“Huh? Oh!” Sunset Shimmer glanced down as the glow faded from around her friend, and with both hands cupped breasts larger than the basketballs Rainbow Dash from their old world was often seen with. “Ha, yeah, forgot I’d have these back in this world. Missed ya, girls.” She hefted them a little higher and barely had to tilt her head forward to give them a kiss to the top of each lovely orb.

“But… they’re bigger than your head!” Twilight pointed with a slightly shaking hand.

Sunset looked back up at her friend and nearly burst into laughter, wrangling it down to just a snicker. “Um, Twi, you might want to check your own.”

Twilight looked back down to her own, back to Shimmer, then back down again before reaching to cup her own massive pair, not quite the match of Shimmer’s, but close. “W-wow.”

“What do you think?”

“…” Twilight’s expression went from shock and awe, to concern, to contemplative, to the well worn contemplation look that always brought a smile to Shimmer’s face before Twilight once again spoke, “I believe I have more breasts flesh than all the women at our school combined while in this form.”

“You think so?” Sunset took a step towards her friend. At their new heights and sizes, even at arms length, their new, naked breasts were close enough to brush nipples. Sunset gave a light gasp, and Twilight moaned as they brushed together, a shock like lightning moving through both gurls straight through their nips.

Twilight took an involuntary step forward as well, her new hooves lightly pawing the marble floor of the building, her arms moving forward to touch… she wasn’t sure. Her own breasts? Shimmer’s? Instead, she had underestimated her newly enhanced arms and had Shimmer in a hug, crushing their four breasts together, shocking both women at the sensation, and at her strength. Shimmer gave a shudder and leaned forward into a kiss, their spiral horns brushing, a magical and not unpleasant spark running through both women as their magics flared to life.

The kiss was over far too quickly for either gurl’s taste, but Shimmer eased her friend’s concern with a placating gesture. “Ok, Twilight, I know you’ll like this, and you’ve asked in the past why I do it.”

“D-do what, Sunset Shimmer?” Twilight wanted desperately to go back to the kiss, to feeling their breasts dance together. Had she truly been unable to make their breasts dent, even against each other? This demanded more exploration and experimentation.

“Flex in front of the mirror before a workout.” Shimmer blushed but struck a pose, arms held flat out beside her, before slowly, deliberately, curling them back towards her horn, flexing her arms as she did, and tightening her pecks as she went.

The effect was amazing and dramatic. What had been corded steel sprang up, expanding, growing in every direction as Shimmer worked until the muscles on her bicep was easily half the size of her breast. At maximum flex, she panted, out of practice at holding such a powerful move, her eyes half lidded as she looked at the flustered, and clearly attracted Twilight Sparkle who’s eyes shined behind her glasses. “How about it, Twi-Twi? Wanna try?”

Soon both gurls were flexing, twisting and turning at the waist to show off to each other from as many angles as possible their incredibly blood pumped muscular curves until neither gurl could handle it anymore and they came together in a kiss, their flexed arms caressing each other’s firm tits and Shimmer quickly pulling Twilight into something her friend had never experienced before, and Sunset sorely missed, an orgasm delivered purely from flexed muscles and sensitive, firm tits dancing together, causing both women to cry out in an orgasmic whiney.

“Whew! That was… Mmmm… exactly what I needed. How about you, Twilight, still fascinated by your own tits?” Sunset gave a lopsided smile, her heart still pumping from their mutual orgasm.

“Well, as impressive as they are, both of us aren’t as impressive as her’s.” Twilight gestured absently with one hand, while adjusting her glasses, still looking down her nose… her muzzle, at breasts she calculated were 25% more voluminous than her own head.

Sunset on the other hand turned quickly, her eyes instantly going to the source of a loud EEP! and flutter of feathers that accompanied it. She felt a smile come to her own slightly projected mouth, lopsided but heartfelt, as her eyes fell on the yellow feather’s and peaking of pink hair behind them as Fluttershy did her best to hide behind her wings, though the pegasi’s own torso dominating breasts were just too large and projected two far forward to really be hidden by the wings.

“Hi, Fluttershy.”

“S-Sunset Shimmer?” A pair of blue eyes blinked between two slightly parted feathers before vanishing again. “Is-is that you?”

“It is.” Knowing her own world’s counterpart to the fluttery, shy Pegasus, and kindhearted soul, Sunset Shimmer knew exactly what to do to show she was a friend. Being careful of the other poni-gurl’s wings, Sunset Shimmer stepped forward and gathered the other woman up in a hug, enjoying the warmth of the massive woman’s breasts, feeling her big heartbeat right through them. Soon the wings parted and instead encompassed both women from the boobs up. “You ok, Flutters?”

“Y-yeah, but why does Twilight Sparkle have those things on her face?”

“Huh?” Sunset glanced back to Twilight, stopped by Fluttershy’s wings before looking back to the pink haired Gurl. “Oh!” She pulled Fluttershy into a tighter hug, loving the feel of Fluttershy hesitantly hugging her back, knowing the Pegasus was always so careful with her own powerfully built arms. Slowly and carefully pulling out of the hug, and Fluttershy’s feathers, Sunset Shimmer gestured to Twilight, who was experimentally lifting first one, then the other, letting them drop one at a time as if testing their bounce. “Fluttershy, allow me to introduce my good friend from another world, Equestria High’s own Twilight Sparkle.”

Twilight finally looked up for the first time, blinked once owlishly from behind her coke bottle glasses, and thrust a handout to Fluttershy to shake, just how Rainbow Dash had taught her in ‘how to make new friends, with assertiveness and 20% more coolness. “Hi, what was your name again?”

Whether it was realizing that the other woman was not in fact her good friend, or just her usual fear of abruptly meeting someone new, Fluttershy again gave a shriek before hugging both her large breasts, even her own arms struggling to wrangle the pair of breasts so quickly, hugging them so tight her boobs went up to her chin, which quickly vanished as Fluttershy face planted into her own cleavage before once more hiding behind her wings.

“…I’m sorry, what was that?” Twilight blinked, leaning forward slightly, hand still extended.

“mrmmhrmf.”

“I’m sorry?”

“Hergermuffle.”

“I um… ok. N-nice to… meet you?”

“EEP!” And the wings gathered a little tighter around other woman, her arms and tits visible under them, muscles straining with veins standing across them at how tightly Flutter was holding them.

Twilight looked back to Sunset Shimmer who offered her a trademarked lopsided grin before shrugging her own shoulders, both of them briefly hypnotized as her breasts briefly parted before smacking together like two steel balls wrapped in velvet. “You get used to it.”

“Well, if you’re anything like my Fluttershy, I’m sure we’ll get along great! I heard you like animals too?”

“Y-you… like animals?” The blue eyes once again peaked out from behind yellow wings.

“Oh yes! And with this being a whole new world, I can’t wait to find out what differences in evolution or biology will have occurred. Do you have any of Lagomorpha Oryctolagus cuniculus?”

“Bunnies?” The wings parted further, and the shielding of large breasts was relaxed as Fluttershy raised her head back up.

“Yes, of course.”

“Oh yes! We have many varieties. Would you like to meet Angel?”

“Is he your bunny?”

“YES!”

“I’d love to!” The two women moved out into the hallway, talking closely about differences or similarities in this species or that, leaving Sunset Shimmer in the mirror room, shaking her head and smiling before filing them out, enjoying the novelty of once more using four hooves to move around, and using her own magic to shut the door behind her.

~

“What do you think, Twi?” Sunset Shimmer leaned over to her friend. They were gathered around a large, round table as food, mostly apples, oats and a bowl of crystals for the most ripped… and hung… dragon in this or any locally known kingdom.

“It’s like a rainbow of mammary glands and muscles.”

Sunset shimmer had to agree. On their left and moving clockwise around the table was first the yellow toned Fluttershy, by far the bustiest in the room, and having to rest her large orbs on the table. It was the first time the ladies noticed they were so firm they actually didn’t conform to the table, instead of simply sitting as two orbs atop the table.

Next was the white toned Rarity, her nipples artfully hidden by a scarf that still served to emphasize her artfully flowing pair that perfectly topped a pair of abs that Twi and Summer knew the Fluttershy of their own world would kill for.

Speaking of Dash, the next Gurl bore a striking resemblance, with short rainbow-colored hair and blue breasts that seemed to be constantly in motion. Currently they were partially obscured as her bicep rippled and corded forearm flexed as she arm-wrestled the next girl.

Bustier and with larger muscles, but still straining against Rainbow Dash’s strength, the veins on AppleJack’s breasts stood out in sharp contrast to the wonderful, proud tits she possessed. “Come on, give it up Rainbow, that male’s cum is all mine!”

“Like you need to get any bigger and slower AJ.” Dash quipped back as she strained back, gritting her teeth.

“They’re talking about Arthur.” Pinkie Pie offered, though it was hard to look up to her muzzle as she kept playing with her nipples absently, her strong hands seeming to always find their way to her pink tips as she fondled herself while watching the other two fought.

“I’m sorry, what?” Twilight blinked, a bit shocked at the open language the other woman was using… but then she remembered the last sleepover with her world’s Pinkie Pie where the woman had spent at least two hours discussing the best way to give a guy a titfuck while openly playing with her own topless pair.

“Oh, our Twilight found out that a human’s cum can make us temporarily grow bigger, stronger, bustier, you know.” Pinkie shrugged, pulling up on her nipples to lift her breasts to match the powerfully built shoulders movement. “And since we’ve got Arthur right here…”

Twilight glanced even farther to the right, next to Sunset Shimmer and between her orange friend and Pinke’s own pink form, was what looked like a stallion’s wet dream of Twilight, which was to say, Princess Twilight in all her Alicorn Glory.

Twilight adjusted her own glasses and made a quick calculation that the other purple Gurl had 100% more tits, 50% more muscles and 25% more height than her own ‘unicorn’ form. Though it was hard to get a really accurate measurement of any of those things, as the other woman seemed to be in the middle of giving a pale skinned otherwise normal looking man standing on the tabletop an incredible blowjob, made doubly shocking by the fact that the man seemed to have a cock as long as his forearm and twice as thick and Princess Twilight seemed to have no problem taking him down to the wonderful, large cum bloated balls.

Sunset Shimmer simply blinked. “Wait, what?”

“Yeah, Arthur’s from this other land with crazy stuff like Tigurls and Cheetahgurls and such. We think it’s where Zecora comes from, she seems to have a twin sister named Maziwa from there who got to like the size of a mountain before!” Pinkie offered.

“Wh-what’s Twi- I mean, what’s Princess Twilight up to then? I wouldn’t think she’d want to get much bigger.” Sunset asked, deciding against asking Princess Twilight anything when her mouth was full. The Brainiac was likely to go ahead and answer, and that wouldn’t end well…. For the male.

“Yeah, she’s already having problems fitting through doors since the whole elevation to Alicorn thing. Na, she’s just keeping him on a hair trigger so the winner can get her reward right away. He seems to like us big and she’s the biggest gurl here!” Pinkie grinned, mashing her tits with her powerful fingers, the veins on her forearms popping out with the effort. “Execussssse me, I’m gonna cum now.”

With a loud squeal, of course Pinkie’s a screamer, Twilight thought to herself, Pinkie Pie loudly came. A moment later Rainbow Dash shouted as Applejack shouted in triumph and smacked the blue fists into the table with her own orange one.

“Ha! I win!”

“You cheated!”

“Tarnation, Rainbow Dash! I did not! I won fair and square!”

“Oh yeah! Then why did you tug my nipple?”

“Oh horse apples!” Applejack pouted. “That wasn’t cheatin’, I just couldn’t resist! Your apple cutters were just so big and hard and I wanted to-”

Applejack gave a startled yell as Rainbow Dash shot forward with both hands and yanked hard on Applejack’s own pleasing pair, giving the other poni-gurl a loud orgasm. “HA!”

“Ok you two.” Princess Twilight pulled back, using her powerful hand to keep working the male Arthur’s cock as she used her mouth for talking. “Looks like that contest was a wash so the first draught of the night, I think, should go to our guests.”

Sunset Shimmer burst out laughing while Twilight blushed and adjusted her glasses, her eyes vanishing behind them.

Shimmer took a moment to get herself under control before replying, “thanks Princess, but I think I’ll offer my share to my bestie. Besides, she’s got some growing to do to catch up to you.”

“Wh-what?” Twilight’s head spun around to face Sunset Shimmer just in time to find the red head pushing Arthur cock first into her mouth. Twilight at first gagged but shooting Sunset a look she quickly took up the task, grabbing Arthur’s rod with both hands and working him, trying hard to remember how Pinkie and Rainbow Dash had debated was the best way to work a cock. Despite her inexperience, and inability to take as much of the length as the Princess had, she made up for it in vigor and imagination, and was quickly rewarded with AJ and Dash’s desired creamy prize.

And what a blast of cum it was! Had her head been screwed on straight, Twilight would have tried to gauge the volume, but as it was she was suddenly, incredibly, happy to have her new stomach size as even the powerful horse belly wasn’t enough to keep up with the flow of cum she was gulping down, her soft and furry belly groaned and gurgled and moaned as it expanded, veins appearing all over her belly as it filled and expanded.

With a low moan, Arthur gave his last spurt and fell back, Sunset Shimmer catching him with her orange magic and quickly into her own well-muscled arms. Twilight stumbled backwards herself as his cock came free from her lips with a wet plop.

Somehow, she hung onto consciousness as she gave a low moan and flexed her arms, her belly gurgling as it absorbed the strange male’s cum. She flexed her powerful biceps and Sunset nearly dropped Arthur in shock as Twilight’s growing arms drew everyone at the table’s attention.

Twilight was… ripped! With abs that would give earn some welcome applause from Rainbow or Applejack, Twilight was shocked at her own sudden six pack. Just as suddenly as they appeared, her abs vanished as her breasts gave a plop noise and expanded in size. Rarity openly gave a cheer as veins suddenly appearing across Twilight’s tits as they grew to match even Princess Twilight’s in size before the growth spread out all over her body, boosting her in height up to the Princess’ own statuesque, even her horn seeming to add inches to it.

“Darling, you look delectable!” Rarity couldn’t help but run her own sinewy hands across her under boobs, stroking across veins and up to her nipples, giving a quick, small, but sympathetic orgasm to Twilight’s growth.

And not to be forgotten, Twilight’s arms gave one last burst, expanding massively even as vein’s crisscrossed over her poni lower half, and she flexed with biceps nearly higher than her head. “YES!”

“Y-yes is right!” Sunset, the only other one in the room who hadn’t seen or previously experienced a cum induced growth burst was shocked at the sudden growth of her bestie. The rest of the poni-gurls gave polite applause to Twilight’s new dimensions, AJ and Dash giving a decent whoop at another gurl joining the ranks of the musclebound giants.

Princess Twilight took the opportunity to step next to her double, the two gigantic gurls marveling at the fact that for once, the Princess wasn’t the largest poni-gurl in the room anymore, and despite clear differences, such as Unicorn Twilight’s arms being much larger, her leg muscles more defined, and Princess Twilight’s breasts being far larger, and overall poni-gurl body having more muscularture to support her massive wings, the two looked nearly identical, shocking the room with just how much the two really were twins.

Emphasizing it, the Princess sidled next to the glasses wearing Twilight on the right, the two automatically sliding an arm behind each other’s incredible backs, their hands dancing across the veins and muscles nearly hidden by long hair, and their four breasts forming a row of delectable delights. The Princess got a sudden look on her face, remembering the first time she and Rarity had first met back when they were both unicorns. “Twilight, now that you’re a ‘big-gurl’ want to see an interesting phenomenon?”

“Yes, quite.” Twilight answered without hesitation.

Twilight raised her right hand and brought it up the breast on her side, all four breasts were forming three deep, dark inviting cleavages and she made sure the two gurls were hugged close before she tried the trick, and flexing all her arms strength into one spot, bent a finger and FLICKED the side of her right tit.

The skin didn’t even dent with the hit, though the room heard it as sharp as thunder crack. The part that shocked the room, especially the science minded Twilight, was that all four breasts gave no indication that anything had happened, save the breast on the far left end of the row, Twilight’s left breast, giving a sudden bounce to the left before smacking back against her own right breast, and the shockwave invisibly passing back to the right, through Princess Twilight’s left tit before making her own right give a light bounce, not even a quarter as big as the initial bounce.

“Are our breasts truly so tightly packed and dense?” Twilight marveled, caressing her left orb with her own free left hand, her right hands still absently caressing Princess Twilight’s right ‘hip’ as it were.

“Ha, and here I thought you’d ask about the required strength and power necessary to pass a shockwave through that much breast flesh to-” While the rest of the room enjoyed the spectacle, having not one, but two nearly identical Twilight’s in the room, Alicorn or not, was enough to make Applejack roll her eyes as the two purple gurls dived into the physics and properties of their own breasts.

“Only these two egg heads could make tits that are that big and firm boring.” Rainbow Dash remarked, flicking AJ’s nipples and earning herself a micro-orgasm from the sensitive earth-poni-gurl. Applejack would have responded to the sudden, harsh but not unwelcome attention, but their eyes were drawn back to Twilight flexing her left arms and then unleashing her own flick to her left tit, giving a slight yell in orgasm at the hit to her sensitive breast, everyone admiring how Princess Twilight’s right tit gave a mighty bounce in response.

Of course, the human male in the room felt his cock throb at the sight of so much muscle and tit and couldn’t help but interject.

“R-ready for round 2?” Arthur hesitantly smiled at the unicorn-poni-gurl, Shimmer, that he was still held by.

“What? Already?” Shimmer glanced down to the male, more than a little surprised. In her social climb in a previous, power hungry life, she’d sucked more than a few cocks and in her experience most men were ‘one-and-done’… with a single exception, but even he would have taken a few more minutes to be ready for another round like Arthur had just offered.

“Oh, uh, yeah.” Arthur blushed, looking down from Sunset’s eyes, his own falling upon her own rippling muscles and powerful breasts, which his hard, naked cock had found itself between as Sunset Shimmer had tucked him between. “I could… uh… go at least five more times like that before I need to rest. You see, I had some of Fluttershy and Rarity’s milk earlier and-”

“Enough SAID!” Sunset shot a quick look at the two women, shocked that neither woman showed any signs of having been milked at all. If anything, Fluttershy looked even fuller than when they’d met in the mirror room. And with that, Sunset Shimmer flexed her pecks, quickly trapping Arthur’s cock between them without any need of using her hands to hold them together.

Instead, her hands supported him and used him to fuck her tits, a solid foot of cock appearing and disappearing above her own spheres as she slid him back and forth. Each time his cock appeared, it quickly vanished into her muzzle as she gave Arthur his first Poni-gurl titfuck.

“Now why haven’t I thought of that before?” Rarity smirked as she gave her visible underboobs a caress and boob-flexed in sympathy to the other unicorn.

“Well, a proper titfuck is something that is great to give but, you know…” Fluttershy blushed. “Well, a rarity.”

Rarity couldn’t help but laugh at Flutter’s unintended pun as the other gurl blushed.

Twincest is Wincest

Author's Note

The gurls get up to even more cock sucking fun, while the Twilights' get a lot closer than either thought possible.

Twincest is Wincest

The gurls all watched as Sunset Shimmer worked Arthur’s incredible cock. Her fingers playing across the veins that covered his cock like she was playing a flute, drawing a low, masculine moan from the man.

The two moved together in harmony and every gurl present felt themselves getting wetter just watching Sunset Shimmer work. Every movement, every flex of muscle and dance of cock and tit a sensuous, sumptuous feast for the eyes. Rarity and Fluttershy started leaking milk in sympathy, just a few drops but it was there. Applejack as the only other milker in the room would have leaked, if Rainbow Dash hadn’t flashed across the room to her orange tits in a flash and begun sucking on the nips so quickly it seemed like she was sucking both at the same time.

For Sunset and Arthur though, the rest of the meeting room faded away, Arthur’s whole world was just orange tits, cock, and Sunset’s eyes as she looked up from his cock to blushingly meet his own eyes, and her whole world was just his cock between her tits, and between her lips.

All the other gurls gasped aloud when in a sudden burst, Arthur came and Sunset began to greedily gulping the first load before starting immediately returning to sucking his cock, even as she began flexing and growing, earning a cheer from the crowd as the other gurls all snuggled a little closer, powerful muscles flexing and fingers caressing heavy tits as they all watched.

Even as she sucked and worked Arthur’s cock, her arms pumped bigger, flexing larger and larger, her tits gaining more veins and nearly doubling in size as her abs gave a burst and became so well defined you could shred cheese on them. She had to readjust her stance, and Rarity gave a low orgasm of applause, as Sunset Shimmer rose above the table, becoming even taller in horse body than Princess Twilight was, her horn taking on it’s own orange glow despite no magic being in use. She kept flexing her arms, smiling around Arthur’s cock at how Arthur’s manhood throbbed in sympathy seeming to grow with each of her own growing flexes.

But despite how all the gurls were enjoying the blowjob titfuck and growth, Princess Twilight was frowning and had turned her head to her nearly-twin-glasses-wearing counterpart. “Twilight?”

“Y-yes, your ladyship?”

Princess Twilight blinked before grinning and giving the other Twilight a hug, her massive arms wrapping around the smaller woman, Twilight’s own matching her a second later in a powerful hug. “Just Twi is fine.”

“S-same.”

“Well, Twi, umm… I’m concerned about Sunset Shimmer and her... sudden cum guzzling.” Princess Twilight glanced back to the orange unicorn, her eyes going wide “She’s my friend too but… she hasn’t previously handled… having too much power well. And she’s still going. I fear she might intend to drain Arthur, and none of us have managed that yet, even working together. She could end up bigger than the entire castle!”

Twilight felt an echo of herself, and of Midnight Sparkle, her super strong, super muscled, and super self-centered alter-ego that nearly consumed her, and she wanted desperately to save Sunset Shimmer from anything, even herself. “How can I help?”

“I think I have an idea, using your science brain and my magic brain together, but just in case…” Princess Twilight turned and shouted, “SPIKE! Meet me and Twilight in the mirror room in five minutes.”

“Uh, sure, Twilight,” Spike said, distractedly staring and stroking his own dragon cock, his own muscles flexing as he leaked flaming precum watching Sunset Shimmer swallow her second load and surpassing even the Twi-twins in size. “Be… right… uh… there…”

“And hold back on too much of that.” Princess Twilight added, noting the cum. “We might need that. In fact…” With a surge of magical power, a cockring appeared around the base of Spike’s multiridged dick, holding the cum inside of those balls, “I’m sure we will.”

~

When Spike came into the room Sci-Twi and Sunset had entered their world from, he found the ‘great mirror machine’ as he oft thought of it, in a general sense of disarray. In the middle of the room, working on the various bits with all four hands, was Twilight Sparkle times two. It took Spike a moment to divert enough blood away from his cock… the sight was just too cock-hardeningly good, to really sort out what he was seeing.

The two Twilights, Glasses-yes-wings-no and Princess Twilight or…. Sci-Twi and Pri-Twi as Spike decided to shorten it, were working together so closely they seemed to almost be using all four arms without asking each other what they needed, and instead were talking a mile a minute about dimensional physics, one from a science standpoint the other from a magic standpoint.

Either was over Spike’s head, but both? That just made his head spin, and not in that fun-way like when one of the gurls gave him a good blowjob. “Uh girls, everything ok?”

“Oh of course, Spike!” They said in echoed unison. “We’ve got this sorted and almost…. Done!”

The whole thing suddenly gave a purple glow and pulled together, even as Sci and Pri-Twi stepped apart, grinning at each other. Their muscles were pumped from the work and their breasts rose and fell in unison as they puffed hard from restoring and rebuilding a dimensional traversing magical machine.

The fact that they were breathing so hard that their massive breasts actually bounced against each other with each puff, despite the fact that their heads were feet apart, did nothing to divert the blood flow from Spike’s cock. “Uh, so what did you do?”

“Oh Spike, we just said what.” The two rolled their eyes but grinned at each other.

“Ok so… what do you need me for?”

“Basically, we’re worried about how fast Sunset Shimmer is growing and we’re going to need your cum to keep up.”

“But there’s two of us, and only one Spike cock.”

Spike frowned. “We’re not doing the dual cock thing again. That was... too much for me.”

“Oh don’t worry, we’ll keep you to one, and we’ll need our mouths to drain Sunset so we’ll need you to put it directly into our womb.”

“So we’re going to use the dimensional portal to partially fuse so we have one pussy for you to fuck us both with!” The last part was said in unison as they grinned at each other, before Sci-Twi’s face somewhat fell.

“I never thought my first time would be with my lower half turned into a horse, with a male dragon, and while sharing a body with my alternate dimensional self.” Blushing, Sci-Twi looked to Princess Twilight and saw the mirrored smile and blush upon her semi-divine countenance.

Princess Twilight shrugged but leaned forward and gave Sci-Twi a kiss, muzzle to muzzle. “Don’t worry, Twilight. Your first time should always be memorable and what could possibly be more memorable than sharing it with someone special, literally?”

Sci-Twi rolled her eyes but smiled, reaching out to give the bustier woman’s breasts a squeeze with both powerful hands. “I don’t think that is what’s going to make this memorable, but let’s do this!”

Spike bit his lip, watching the two gurls, one Unicorn, one Alicorn, step into the mirror together and squeal in orgasm as they were sucked into the other dimension.

~

Stepping out the other side of the mirror into the front of Equestria High, Twilight blinked and adjusted her glasses before glancing to her right at the blushing woman sharing her shoulders. Thinking quickly, Sci-Twi pulled out her phone and just like Rarity had taught her, shot the perfect selfie, lips pursed included. Pulling the phone back to herself and holding it such that both she and her… partner could see, they checked out what their new form looked like in her world.

They were sharing a pair of incredibly long, insanely well-built legs, barely contained within the tiny purple skirt that struggled to contain their wide hips. They could tell that they were ‘going commando’ from the slight breeze the caressed the firm butt cheeks that they could feel were slightly on display.

From their tightly built waist two sets of abs sprung up, spreading into two fully separate torsos, each having two of the most powerful arms in the world, arms bigger than what she estimated their separate legs would be. Their breasts, despite being smaller than in the poni-gurl world, were still at least as proportionately bigger from when Sci-Twi had first stepped into that other world.

What really surprised her was how much leaner and stronger their faces looked as 'Equestria Gurls’ than the last time she’d been one, and the obvious differences and similarities the two women had now that they had a bone structure her mind was more used to parsing. We really look more like twins than the same person, don’t we? Sci-Twi theorized. Maybe that should be conjoined twins…

“Well I’d say that was a success.” Pri-Twi nodded to herself, noting how their ‘smaller’ breasts were nearly bursting out of their tight blouses in a way that she wasn’t sure if Rarity of either world would approve or reject. She did think that Sci-Twi looked quite comely nearly ripping through her shirt with just her powerful tits, a tingle in their shared pussy letting her know that Sci-Twi probably felt the same about her own orbs. “Ok, shall we head back and see if we can save our friend?”

“Wait, there’s something I want to try first!” Sci-Twi paused their turn towards the portal to reach up and grasp her necklace with the hand on Pri-Twi’s side. “Ponnnnnyyyy-UP!”

Pri-Twi was about to inquire on if it was Rainbow Dash or Pinkie who’d come up with that saying when she felt the magic of friendship flow through her… them… both? Both.

As the glow faded away, the two women stared in shock at their combined body. They were over sixteen feet tall, with breasts larger than even their pony-gurl forms. They flexed their arms, both women looking to their closest bicep in open mouth shock before turning back to each other with huge grins.

“How about we go back through the portal super charged like this?” Pri-Twi presented. “Could be an interesting experiment to see how this translates in the other universe.”

“I’m game if you are.” Sci-Twi bit her lip, and just as they were stepping back through the portal, pulled her twin into a kiss, using all the strength she could, knowing she wanted at least one really deep, pussy wetting kiss with this woman while like this before they went to the other world.

Pri-Twi was surprised but quickly met it with just as much fervor, the two women squeezing each other tight with their four powerful arms and mashing their heavy breasts together. They went to fall to the ground and continue their mutual pawing, instead falling into the mirror portal together, squealing into each other’s tight, strong lips, around each other’s exploring tongues in the sudden orgasm that filled their shared pussy.

~

“Oh… my… huh?”

“Uh, Twi?” Spike reached out and hesitantly touched his friend’s shoulder as the poni-princess came back to herself. “You ok?”

“Of course, Spike, why wouldn’t I be?” She pulled herself to her full, insane height, legs bigger and thicker than an entire pack of Clydesdales, her doubled spiral horn thrusting to the ceiling so fast and hard, Spike was unsurprised when it actually pierced it, forcing the poni-gurl to duck her head slightly as she stretched her incredible arms, twice as big and thick as Princess Twilight had been earlier. And the breasts…

The breasts were like the rising sun, a sight to behold and yet so grand, so wonderful, that Spike wasn’t sure if he wanted to keep staring, or look away. “But… what about… ummm… there being two of you?”

“Oh, don’t worry.” The large woman smiled, reaching up to absently adjust her glasses before reaching further up and readjusting her crown. “We’re both in here. Our brain is kind of a Venn diagram at the moment, with 90% overlap, and 5% Princess and 5% Equestria gurl. I guess I… or we? We must have miscalculated a bit, or maybe Sci-Twi and Pri-Twi were more mentally alike than we initially realized. Could have been that shared orgasm as we fell through the mirror too.”

Spike swallowed hard as the incredibly powerful woman leaned forward, her breasts so firm they didn’t even jiggle, but first underboob, then full boob filled his vision before Twin-Twi’s face filled his view. “And now, it’s time for that wonderful cock of yours to fuck this gurl nice and hard.”

~

As a glow that hardly anyone noticed to Spike’s eyes fade, across the kingdom a similar glow faded from Princess Celestia’s eyes and she turned and called out to Luna, awakening her sister, Princess of the Night.

The dark furred little sister stepped into the room, her massive moon sized tits (or so many of their followers whispered to each other) entering the room far before the yawning princess did. “What is it, sister?”

“Lulu, I’m afraid we may have to intervene with my favorite gurls.”

“But Tia, you said we shouldn’t intervene with what they’re doing, that they may find the secret of-”

“Not only must we intervene, Lulu, we may need the help of… Celestial Eclipse.”

Luna gasped, but felt her heavy tits churn, and nipples sprang to instant hardness as her grand orbs inflated with milk at the thought of their ultimate form.

~

It hadn’t quite been true, what Dual-Twi had told Spike. Her brain wasn’t a Venn Diagram, per se, it was more like there were simply both Twilight’s talking, in unison, and mostly saying the same thing. They were mentally what Princess Twilight had been hoping for physically, a single body with both heads, mentally speaking. Twilight’s personalities separate and equal. But then, he was a boy dragon after all.

Instead, Twin-Twi, as she thought of herself, turned her attention to the fit young winged gurl who’d just darted into the room.

“W-woah. What happened to you?”

“Never mind that, Rainbow Dash. What’s going on in the table room?”

“Oh, uh, Sunset Shimmer just got Male-Arthur to swallow another load of milk and I think she’s about to start growing again before going in for thirds on a cum blast, and I wanted to check and see if… well, you guys wanted to see, because I’m sure it’ll be one of the most awesome things since Luna had that dream that all of us were growing huge tits and-”

“Made us all have an orgy, I remember.” Twin-Twi blushed as internally Pri-Twi shared the memory with Sci-Twi, both women briefly shocked as sharing the memory made it like Sci-Twi had been there engaging in some big titted lesbian horse action in the dream plane along with her Princess Twilight and the others. “Ok, so we need to hurry!”

“Yeah! You don’t want to miss this!”

No, we really don’t. The two Twi’s looked to each other mentally, biting a lip before they had to teleport through the doorway, as there was no way she could fit anymore at her new size. Spike, the last one out of the room, gave a whimper as he glanced down at his heavy, full balls.

~

The Trio rounded the corner into the ‘table room’ just as Sunset Shimmer gave one final swallow and moaned as Arthur’s cock popped free from her lips.

Sitting him aside, she reached down with one hand to caress her incredibly well filled belly. Moaning aloud again, she felt the cum begin to be absorbed into her, first in her legs, the four hooved appendages, not just her clompers but her whole legs groaning as they grew more powerful and thicker, surpassing all but Twin-Twi’s mega legs, hinting at what was to come.

Her hugely inflated belly gurgled and shrunk, but not from absorbing more cum, but from her belly becoming more powerful, tighter, stronger, able to better squeeze that cum filled contents, veins rippling up across her surface as her full horse body seemed to inflate larger and stronger than anyone else in the room, and rising her orange human-ish torso up higher.

She sighed briefly, a slight shiver passing up her spine before she took in a full breath. With a mighty yell, she flexed again, her breasts seeming to leap forward on her chest, expanding faster and stronger than any other breasts, more than any of the five girls at her feet… well four, and a nearby fluttering Rainbow Dash, combined, before growing AGAIN, growing much larger than Sci-Twi and Pri-Twi had before their fusion.

Sunset caressed her orbs as her muscles rippled across her back, and down her arms, until her hands were finally strong enough to ALMOST dent her firm, vein covered tits. She yelled in success as the main five cheered along. AJ gave a few whoops, mixed with Pinkie Pie’s cheerleader-esque cheers. Rainbow Dash zipped loops around the large Unicorn Gurl, her fingers and feathers tracing enticing lines across the incredible bumps, ridges and curves of Shimmer.

Twin-Twi had to admit, the gurl looked good! Sunset Shimmer was a study in bronze of everything the gurl form could be, proportionately as large of tit as Princess Luna.

No. Wait, those wonderful, dense tits are proportionately at least 14% bigger than mine, possibly 20%. Sci-Twi’s mathematical circumference measuring inserted into their thought process while calculating the head-to-tit ratio and comparing it with her own.

But then, eveyrone’s eyes fell to Arthur, his heavy moans pulling every gurl’s attention, their pussies twitching in response before they spotted the source of his distress.

His balls were nearly the size of Celestia’s Tits!

“Celestia’s Tits those balls are big!” Rainbow Dash bluntly said, unknowingly using one of her favorite curses in reference to both the situation and the size of those balls.

“So… big…” Twin-Twi sighed, her hand feeling up one of her massive tits.

“Looks like I’ve got a bit of growing to do to catch up to you, Twi.” Sunset said, acknowledging the other woman, the fused woman, for the first time. “Arthur here just had his fill from my tits, and I can’t wait to see what a third load of cum from him does!”

Using her new muscles, she scooped up Arthur, actually having to flex her magical power to enhance even her own powerful arms to really lift the massive balls. Cupping them in both hands, she hungrily took his cock into her muzzle, sucking him deep down her throat, and using her lungs to put the most intense suction she could, delighting at the instant reward of pre-cum, making her nipples pearl with milk.

Milk that the mere scent of was like an aphrodisiac for all involved.

Twin-Twi gasped as she saw Sunset set Arthur down on her own tits, by the balls. Her hands caressing all over the huge, heavy balls. Seeing where this was going, Twin-Twi poured all the magic she could into it, and teleported them all outside…

~

With a loud puff of magical smoke, all seven girls reappeared outside, Twin-Twi flexing her muscles hard at the magic that had coursed through her fused body to be able to transport that much gurl in one go.

“I didn’t know you could do that.” AJ blinked, checking herself over. Once she’d been teleported with Princess Twilight and had... a bit of an accident. Being a pegasus had been fun, but Rainbow Dash had quickly wanted the wings back.

“I didn’t either!” Twin-Twi caressed the side of one tit, still puffing a bit. “Just glad to get us all outside before-”

“WOOO!” Pinkie shouted, crushing her tits to her chest as she shouted, her powerful arms nearly exploding in muscles with the effort, her veins pumping in a massive ripple along with her speedy heartbeat. “Suck that DICK!”

All eyes turned to Sunset shimmer as she did an admiral job of holding her breath, deep throating the massive schlong of Arthur, his cock visibly bulging her throat, the veins that crisscrossed that dick standing out even through her neck. Her powerful hands clutched his balls, her arms bulging obscenely as she squeezed his balls, getting a glob of cum from the pressure. The effect of the short little burst was immediate, her tits growing again with a bulge starting on the base and bulging out to her nipples.

Arthur started with a moan from his nose, slowly turning it into a loud, throaty moan as he felt his cum starting to boil over from Sunset Shimmer’s urgent throat fucking. “S-Summer? I’m gonna… Gonna…” Suddenly he saw a glow and opened his eyes enough to see an orange glow around Shimmer’s horn and a smirk around his cock as he suddenly felt every inch of his balls caressed by a thousand powerful hands! Sunset was using her magic to hold up his balls as she used her actual arms and hands to pose and flex for Arthur’s delight.

And delighted he was! He roared as the first blast of cum erupted from his cock, bulging his cock to nearly twice it’s size in one thick glob of cum pushing it’s way in a pulse, Sunset groaning as he stretched her throat. The thick loads of cum, one after the other, pushed their way into Sunset’s body, her eyes growing wide as Arthur surpassed any previous amount she’d taken… even at that one football game when she was running for home coming queen back before turning good…

Her stomach bulged with cum, groaning, as it nearly burst with the sudden influx of man-goo.

Twin-Twi couldn’t resist and stepped up to the growing gurl, her tits pushing against both the back of Arthur’s balls and the front of Sunset Shimmer’s firm tits, her nipples barely dense enough to dent Shimmer’s tits, and feeling the growing tits pushing back. She reached out with both hands and caressed the massive orange tits, flexing with all her fused muscle to really squeeze the tits she’d wanted to feel for so long, in either of her previous lives.

Twin-Twi’s powerful fingers stroked across the massive, growing expanse of Sunset’s tits, her thumbs grinding against her areolas as her fingertips traced the thumping veins that worked all over the other gurl’s surface. “So much… magic!”

Still swallowing, Sunset looked up through lidded eyes at the still taller woman’s glasses and crown and smiled, bemusedly, flexing again for not just Arthur, but her best friend as well.

Twin-Twi gasped and reached out, stroking across the powerful arms, “your muscles are higher than your head!”

“Mmmm and I haven’t even gotten my full flex on.” Sunset said quickly before returning to the cock. Relaxing her arms, she focused her eyes, blushing across her muzzle before in a sudden burst, flexing as hard and big as she could. Before Arthur and Twin-Twi’s eyes, she seemed to expand in every direction, absorbing the cum he’d already pushed into her and flexing larger, thicker and bigger.

Sunset Shimmer’s massive shelf of breasts pushed out and up against Twin-Twi, who came to the realization that as Sunset swallowed more and more of the cum from those lovely, veiny, balls, that Twin-Twi was about to become second biggest again. Sunset Shimmer groaned and reached down with hands that now were finding a horse belly so big and large that she could indeed get her hands on the massive bulge in of cum inflated and vein covered tummy.

Sunset groaned as the last spurt of cum filled her belly, her whole form groaning as she tried… failed… and tried again before successfully getting that last massive load of cum down, her eyes watering as she struggled to contain it all. “Tw… Twilight? I think I might… AH!”

Twilight gasped as Sunset’s eyes rolled back into her head. Fearing her best friend was about to burst like the cum filled balloon she’d become, Twin-Twi leaned forward, crushing their tits together in an attempt to kiss Sunset, but found a face full of Arthur’s balls as Sunset suddenly expanded in every direction, especially up, pushing Arthur and his magnificent, refilling, balls back towards the uni-alicorn.

Sunset was flexing, panting, and groaning as she flexed and grew again. Her horn wasn’t just glowing, but seemed to be on fire.

Greedy Guzzling Gurls

Breasts. Arthur’s whole world was tits. First Summer’s growing tits pushing him back towards what he understood was both the purple gurls he’d met earlier today, including the one without glasses who had given him such an exquisite blowjob to keep him edged for nearly an hour, and the other one with glasses who had finally finished him off, had somehow fused together into one super muscular ponygurl.

She sported a large spiral horn and was wearing both the glasses and crown of both gurls, which he supposed was a tipoff that his theory was correct. He looked up at the large gurl who smiled apologetically before giving his huge cock a kiss to the side of one large vein tracing up the side of his cock with her firm lips, the vein larger than both his arms and legs combined, let alone how massive his cock had become.

He wanted to focus on the gurl, her touch, her soft lips, the way her eyes, hidden behind those thick glasses never left his, on the heavy breasts that lifted his balls up. But there was something else pulling his attention away, a pair of massive orange breasts, a wall of tit, headed his way.

Headed his way, FAST.

~

Twin-Twi readjusted Arthur just in time for what felt like a brick wall hitting her massive breasts, tits first, knocking the massive uni-alicorn back a step, her eyes going wide as she found Arthur plummeting from the massive height on the top of her massive tits, nearly 20 feet in the air. His fall was abruptly halted as Twin-Twi’s twin-tits once again met that ‘brick wall’, catching Arthur in her combined cleavage, by the cock!

Twin-Twi gasped as she looked up at the blushing Sunset Shimmer, visible just past the massive cock held in the air between them, and the gigantic tits on Sunset’s side. Those massive unforgiving mass hadn’t been a brick wall, but Sunset Shimmer’s incredibly dense tits. The other gurl was, to Sci-Twi’s quick computations, and Pri-Twi’s matching estimations, 25% taller than the fused gurl.

Sunset’s orange breasts were much larger than that, nearly twice what Twin-Twi shared with herself, and their sudden expansion had been fueled entirely by Arthur’s incredible cum, compared to Twin-Twi that only maybe 20% of her own growth had been.

The difference was dramatic. Sunset Shimmer curled one arm and showed off to all the other gurls, especially for her breast, er, best friends, Twin-Twi. It was gigantic, more muscle in her left arm curl than in Twin-Twi’s combined body. The veins danced and rose across the surface of the arm as Sunset used the last of the cum to push it up even bigger, the massive muscles bulging for the fusion gurl, a deep blush spreading across Sunset’s cheeks and muzzle as she looked at Twin-Twi. “D-do you think I’m big enough?”

“I… There are… No. Words.” Twin-Twi, was breathing hard, panting in passion as she started to reach out to touch those muscles… those tits, but felt a shift in the two heavy balls she had been holding up this whole time just beneath her and Sunset’s tits.

So big, those balls… and growing! The cock was gigantic, and growing as well, rising like a mighty redwood... or library... between their four tits.

Sunset shot her besties a grin and wasted no time. Rocking her tits back and forth and bringing more and pleasure to all three, or four depending on how you were counting, as she ground her tits against Twin-Twi, with a massive cock trapped between them, she smirked around the cock and asked, “How about it, Twi, think you’re gurl enough to keep up?”

A grin that did Rainbow Dash proud spread across Twin-Twi’s face as she gave Arthur’s ball a caress with both her hands, feeling the powerful veins pumping his balls larger. With a glow from her horn, she used her magic to briefly hold him up as she reached out and grasped Shimmer by the wrists, their four tits so large, their muscles so big, that that’s as much of each other’s arms as they could reach. Flexing their muscles, the two gurls pulled each other as close as they could with so much dense tit in the way.

Releasing the magic hold on those heavy balls, Twin-Twi grinned nearly from ear to ear as she had calculated correctly. Balls as big as Luna’s tits might be pulling down, but their four mega tits was enough to hold that cock between them, and Arthur held up, by just tits.

But Twin-Twi knew she needed an edge. Glancing to the right and ready to activate plan ‘Spike, fuck me hard’ she was utterly shocked to see the buff, young dragon stud completely conked out, a dazed and happy expression on his face, tongue lolled out and a thoroughly drained quad balls that dragon’s often sported, and a cock that could choke even a ponygurl flacid and draped over one leg.

Standing next to the knocked-out dragon was Rarity with what was clearly a belly full of dragon cum, her stomach bloated and clearly glowing as if she’d swallowed a few gallons of lava. The pale unicorn moaned as she absorbed the dragon cum, growing larger and taller, ten… then fifteen percent, her breasts surpassing even Fluttershy’s amazing pair. They were easily half again larger than the timid Pegasus gurl’s own set, with smaller nipples than the much larger so oft-milked pair that Fluttershy sported.

Rarity flexed her muscles as her veins glowed with dragon cum power, as her previously full belly had a minute ago, crisscrossing her powerful arms as she reached a point where they could have competed with even the powerfully built Applejack now. Grinning she relaxed, and with a shout gave a hard flex, her muscles expanding enough that the sudden burst was enough that AJ and Dash took two steps back, glancing to each other and realizing Rarity had just surpassed both their muscles combined in one dragon-cum-fueled flex. Finally, her eyes turned a brilliant blue, sapphires, that had Spike still been awake he would have worshiped Rarity for them alone, if not the rest of the new goddess form she had attained.

“Rarity, really?” Applejack caught her breath and with a light grin, lifted an eyebrow, though the scent of her arousal mingled with other mane gurls as they all gazed upon the alabaster unicorn.

“Please, darling, every good fashion designer knows how to give a good blowjob.”

“Yeah, yeah, being good at sucking is great as long as they’re a… Rarity.” Applejack rolled her eyes but grinned at her friend. “I call seconds when he wakes up again.”

“Hey, no way, I want some competitive tits!” Rainbow said, the squabble quickly pulling Twin-Twi attention away from the mane gurls and back to her own compeTITion, with Sunset Shimmer and the cock held between them.

With a gasp, she realized she’d been losing time, and a thick glob of precum was now visible at the tip of Arthur’s mega log, one the Uni-alicorn was quick to use her magic to get ahold of. It was so thick, and reached so deep, that Arthur felt like his entire cock was being fucked from the inside as Twin-Twi with her spiral horns glowing pulled the thick wad of cum up, pulling even more from the boiling tops of his balls and up his cock, the whole thing bulging with the slow passage of cum up and out of his cock until it was all contained in a sphere of purple magic.

With a grin, the uni-alicorn opened her mouth wide and greedily sucked the wad of cum down, and felt her body responding even as she swallowed. “Wow, even human pre-cum is potent!”

Sunset Shimmer couldn’t help but give a quick laugh, but focused on her friend and the effect the pre-cum was having on Twin-Twi. The fused gurl moaned as she slowly grew bigger. It wasn’t the rapid burst of Arthur’s full load, nor the flamey spurt of growth Spike’s Dragon cum had given Rarity, but a quick prelude of what was to cum, her muscles gaining more and more definition, until her arms were the equals to Susnet’s own, a roadmap of veins crisscrossing the powerful bicep. The gurls watching could see how powerful her back was becoming, Pinkie Pie striking a pose for the other gurl’s where they could see her own powerful back, previously the best of the bunch thanks to her big wobbly balloons, and loudly pondered what Twin-Twi would look like with this pose, arms curled above her head.

While Twin-Twi's breasts did grow, Sunset’s were still far in the lead, but finally the two gurls were eye to eye. The two gurls grinned at one another, feeling at once kinship and a competitive desire burning like dragon cum in their belly.

They started grinding their tight, spherical tits together, pushing their sensitive, dense breasts to the limit around the massive cock trapped between them, their muscular arms hanging onto each other desperately.

~

Beneath those four heavy tits were gigantic balls, large enough to make a goddess, or a Princess, blush. They were larger than even Princess Luna’s tits, putting the heavy cum tanks in the same category as Nightmare’s Moons. Arthur groaned, feeling trapped. Above were tits, bellow were his massive balls, between it all was his cock trapped between four of the most majestic under-boobs he had ever beheld. The pair of purple and orange tits ground together around his cock so fiercely he half expected to look up and instead see a purple and orange swirl of veiny tits, but he was just happy to hug, and kiss, and caress as much as he could reach.

Twin-Twi’s tits felt like velvet wrapped over steal, and he couldn’t help but grip the pumping veins and lick everything he could reach. He could feel Twi shiver with every touch, her skin moving as the four giant tits ground his cock, and her moan was so deep, so warm, that he felt it like a small earthquake through her tits. He echoed her with a moan of his own as his balls began to boil. He was at his limit and knew it, but didn’t know which gurl was going to get what felt like over 300 gallons of cums.

~

Sunset Shimmer was busy trembling her way through an orgasm. While she wouldn’t have traded her years at Equestria College for anything, she’d missed having her poni-gurl body and just how orgasmic it was capable of being. The last time she’d felt this much pleasure had been back in the other world at one of Pinkie’s sleepovers. That one right after Sci-Twi had joined their group permanently, and Pinkie and Rainbow had convinced the newbie that a daisy chain was a must have at any all gurl sleepover. They’d taken turns chaining together until each one of them had been licked to orgasm by every other gurl, and also licked every gurl to a thigh clenching, tit grabbing, ass spanking, orgasm.

But this was just tits. Just Twin-Twi, the biggest and bustiest gurl Sunset had ever seen outside of herself, so big, so majestic, so using her magic to…

To…

Sunset snapped back to full awareness, clomping up from her tit-gasmic induced stupor to see that Arthur was cumming, and cumming, and cumming! Twin-Twi had used her magic to pull his cock through their four smished tits to bury it fully in her own purple cleavage, her mouth now firmly around that bulging, pumping, cum blowing cock!

That greedy, cum guzzling, bitch!

Sunset was just too stunned by the cum-theft, the cock theft, and wanted desperately to yank that massive redwood of dick back through the feet upon feet of purple and orange cleavage so that she got her share too. Instead, she found herself leaning forward, using her magic to push the cock even more towards Twin-Twi, to squeeze her friend’s massive boobs even tighter around Arthur’s cock, and letting go of Twin-Twi’s powerful arms so she could start massaging both those massive balls with her powerful hands.

And what balls they were! She gave an involuntary gasp and took a step back, admiring the massive balls, fingers stroking across the veins before grasping with both hand and giving them a SQUEEZE.

More than a few boyfriends in her darker days had not enjoyed her squeeze, but some part of her knew that not only would Arthur love feeling her work her big, strong muscles and her hands all over his overladen balls, stroking, squeezing, and pushing more cum directly up through his cock and into Twin-Twi’s surprised mouth, he’d be begging for more.

Sunset couldn’t help but give a little laugh as Twin-Twi’s eyes bulged open as big and wide as the rims of her glasses, glasses that had slipped down her purple muzzle. What had been a fountain, became a geyser of cum, all pushing into Twin-Twi’s mouth at once, and Sunset wasn’t going to let the purple princess drip a drop of the well cultivated cum.

~

Twin-Twi moaned and reached down, partly to feel a stomach that Sci-Twi had to be mentally reminded by her Pri-Twi half wasn’t contained under those sexy abs, but in a lower, larger space inside their poni-gurl lower half. Unable to reach it easily, Twin-Twi’s hands fell upon Arthur’s incredible balls. Her fingers traced along the sides, and Sci-Twi ran a quick calculation. When this began, his balls contained approximately 357 gallons of cum. To which the Pri-Twi part of their brain gleefully added, and all of it is going inside this hungry belly!

She couldn’t help but give those massive balls a squeeze from her side.

~

Arthur on the other hand was losing his mind. Four powerful hands were caressing his balls, squeezing him from four separate angles, massive muscles flexing and pushing, forcing his boiling, cum filled balls to push more and more cum up through his cock, pulsing between Twin-Twi’s Tits, and deeper into Twilight’s stomach. He could hear her swallowing, and knew his cum was passing through her long throat as she gulped the gallons of cum.

And more than that, Arthur could hear a sloshing sound… from inside those heavy, purple underboobs he was so desperately clinging to. He was hearing… he could smell… MILK.

~

Sunset watched in awe, still caressing and squeezing Arthur’s balls, but she was in utter shock at just how much her bestie was able to handle. Was Twin-Twi intending to drink it all? Could she? Sunset had been at her limit before! Could her best friend x2 really handle it all? Sunset could already tell the Brainiac intended to try. Did Sunset dare try and stop her? She wanted some of the cum for herself… but to see Twilight get as big as she could... It was just too tempting!

As she watched in indecision, Sunset’s jaw swung open… Twin-Twi was… her belly looked pregnant with a whole herd of muscular poni-gurls! And Twin-Twi wasn’t even half done with those big, cum filled balls!

With a deep breath, Sunset knelt down, moving to her incredible knees and let those heavy balls rest on her tits, still holding them in place with her powerful hands. Arthur’s huge balls were now between her tits and Twilight’s, part of her delighted that her own massive pair was still bigger than her best friend’s, even if one of the purple princess’s arms was enough to lift Sunset in her entirety. Giving one of Twilight’s breasts a kiss, she flexed her abs and did something she really hoped wasn’t going too far.

She stood UP.

The result was that her breasts squeezed those mega balls between her own firm, fit breasts, and Twilight’s pair, turning a guyser of cum into a near explosion. Arthur cried out at the sudden increase of pressure, being stuck as the meat in a tit sandwich between so much gurl. Sunset let go of Arthur’s balls, knowing they were well and truly trapped between her tits and Twi’s, and instead moved her hands up to caress Twilight’s vein covered tits, tracing each one with a finger, until they all inevitably met at her nipples, which she gave a sharp tweak, even as she increased the pressure on those heavy balls, by decreasing the space between the two bestie’s tits.

Then, a new surprise happened, from Twilight’s nipples… in two sexy fountains… was milk.

Delicious, wonderful smelling… milk! Sunset couldn’t help herself but dive face first against Twilight’s right tit and began sucking as much sweet gurl goodness as she could. A part of her mind became aware even as she lost herself in that delightful, wonderful milk from her bestie, that something very important was being said behind her.

It was Pinkie commenting that she had a twitchy tail.

That’s when she heard the massive pair of impacts behind her.