Twilight hesitantly stuck her head through the portal. So far so good, it was still attached to her, her eyes still worked, and crossing them confirmed that her face had swapped out her cute horsey snout for her cute human nose. Presumably that also meant she had her cute human ears and everything else. She allowed herself a slightly smug smile.
Getting the portal working again had been a lot of trial and error and she hadn't really been sure she'd gotten everything right. It's hard to be confident about anything when you're dealing with magic that old and you have to re-write a lot of the underlying spell mechanics from scratch, but everything seemed to be in order so she felt safe enough to lean her torso through.
"Good, it gave me clothes this time," the currently half-pony half-highschool girl noted. That had been an embarrassing failure, although she was pretty sure no one had recognized her. Everything looked normal this time, so she stepped through completely and glanced around. No one in sight, it looked to be slightly before sundown, and the statue's flat grey wall gave no indication of its true interdimensional nature. She stuck her head back through and wiggled her ears at the strange back and forth transformations. "I think we've got it this time, Spike, everything seems stable. Don't forget to reactivate the mirror in one hour." The little dragon waved a claw, "Yeah yeah, I've got it. Say hi to the girls for me, right?" Twilight shook her head, "This is a scouting mission, Spike. I'm just trying to make sure everything is functioning and there are no surprises waiting for us." Her expression softened, "But I will if I see them. Portals closing gotta go! Remember, one hour!" and she pulled her head back just in time to watch a shimmer of light pass over the dull concrete.

"Well, that's that then. Lets go make sure everything is how I remember it." Confidently, Twilight strode out towards the school building. That is, she started to, only a couple of strides in and something felt decidedly not-right. There was a noticeable counter-motion to the swinging of her legs, a motion that didn't stop for several seconds after she skidded to a halt.
Her eyes dropped apprehensively. Cute blue shirt with cute bow tie, check. Tits, maybe a little bigger than before but nothing outrageous, check. Cute little purple pleated skirt with her cutie mark on it, check. Actually, un-check, there was definitely something up with her skirt. Did she not get the clothing matrix exactly right? It was hanging strangely in the front, as if the pleating was bunched up, or it was draped over something...
"No way. That can't be what I think it is." 
Her suspicions weren't hard to prove however, a swing of her hips both shifted that bulge and caused an unfamiliar sensation to tingle its way up her spine. Any last shreds of denial evaporated as a dusky lavender tube of flesh swung pendulously into view.
"Well... That's going to be hard to explain..." 
Twilight was no stranger to the sensation, at least in her normal body. Celestia had called it part of the "princess package," and her soothing chuckle at her own bad joke had been the only thing that stopped Twilight from panicking when it revealed itself. It had been a lot smaller back then though, and the last time she had come to this world the portal had just left it at home. As much as she had grown to love her new appendage, this body, and this outfit were not equipped to handle it. In her quadrupedal form it stayed neatly tucked away in its sheathe when it wasn't needed, but there must not have been room in this body for enough horsecock to hang past her knees to retract like it was supposed to, and her cute little purple skirt was woefully inadequate. It barely even hung past her balls, each step or little gust of wind raising the hem enough to reveal the fat bulges in her cute purple panties.

"Hmph" Twilight huffed in resigned frustration. Tapping on the concrete in front of her confirmed the portal was closed, and wouldn't be open for another hour. Taking another look at her surroundings, Twilight assessed her options. Just because there wasn't anyone around right now didn't mean someone wouldn't be coming by soon, and she was very exposed at the moment, and not in the mood to answer the kind of questions likely to be asked of a girl standing around with two feet of horsecock hanging from her skirt. Her best option seemed to be taking refuge in the school. There shouldn't be many students around this late, and she could take refuge in an empty classroom or closet and wait for her escape route to reopen. As long as she didn't get unlucky she shouldn't have any problems.

Of course, she's not that lucky. The first door she reached was locked, her cock head lightly plapping against the paint as she tugs futilely on the handles. The second too, and she began to despair before spotting an open window partway down the wall. It was higher than her head, but she thought she could reach it, and plans panned out when she managed to get her fingers over the sill with only a small jump and a lot of ungainly flopping. It might not have been the most elegant entrance in the world, but she managed to haul herself up and tumble into the room, landing on her ass against the wall with her legs spread and the cause of all this trouble laid out neatly between them.
"Twilight?"
"Twilight!"
"Oh no."
Of course she's not alone.
"What are you doing here?" 4 voices said at once. Twilight from her position on the floor, and Dash, AJ and Pinkie from where they had two desks pushed together, strewn with textbooks. "Study session" was Dash's answer, and AJ expanded, "We're close to flunking Math, and somehow Pinkie's the one that gets it the best." "Yeah-huh" Pinkie chirped, "Now you! Where have you been?" 
Twilight just sighed. "It's a long story..."

"That wasn't very long at all. Spike broke the mirror while playing hoofball in the attic and it was hard to fix." Pinkie cocked her head at Twilight. "Well, when you put it that way I guess it sounds like there wasn't very much thought put into the scenario, but I've still got almost an hour before I can go back to Equestria and fix this. Want me to tutor you in Math?"
Dash's chair clattered to the ground. "Screw studying, look at that thing!" Twilight blushed. "I told you, it's a-" "It's huge!" Dash interrupted. "You gotta let me get a closer look."

This is not how Twilight expected this reunion to go. She had prepared herself for many possibilities, but standing with her skirt held up and her panties around her knees, cock and balls swaying in the breeze as three of her friends gasp in awe was not one of them. Although in retrospect this isn't that far off from how it had gone back in Equestria. Her friends even had similar expressions. AJ was biting her lip, looking uncertain, Dash's jaw was slack and her eyes wide, and Pinkie was wearing a smile as wide as a mile. And nothing else.
AJ took the opporunity to distract herself. "Pinkie! Where'd your clothes go?"
"I took them off. Don't want them to get messy of course!"
Dash responded without taking her eyes off Twilight's hypnotic junk. "Why would they get m-. Nevermind, stupid question."
"Yeah-huh!" was all the answer she got before Pinkie put her mouth to more valuable use. Twilight had been silent for a while, not sure where her friends would be comfortable going, but feeling Pinkie's tongue stroke the long path up her shaft dragged a moan from her throat and sent blood rushing to her cock. Pinkie kept her mouth latched on as it rose, stiffening and thickening as it went from dangling past her knees to jutting forward like the prow of a mighty icebreaker, accompanied by a chorus of lewd slurps and smacks from Pinkie, moans from Twilight and heavy breathing from their audience.
Pinkie popped off with a flourish of her tongue and looked back at her friends. "Well, what are you waiting for?"

Twilight felt like she should take stock of the situation, things might be getting out of hand. She was naked. Her friends were naked. She was standing, leaning back on their textbook covered desks that now had their clothes draped over everything. They were kneeling in front of her, more than an arm's length away, but still only inches from the slightly flared head of her twitching purple marecock. She was working her hands over the nearest third of her shaft, while they teased the crown. Things were definitely out of hand, but from the lust filled expressions on her friend's faces no one was going to complain. Maybe she could take things a little farther.

Turns out she could take things a lot farther. Pinkie insisted, in fact. Really, there was no way she wasn't going to end up in this position from the start, seated on the desks with Pinkie bouncing in her lap, impaled on a cock almost as long as her torso while AJ and Dash kneel on the floor between her legs and tongue her balls as they dangle over the edge. Pinkie's naked breasts and puffy nipples drawing hypnotic circles in front of her face made it very hard to imagine any other possibilities. Twilight was right were she was supposed to be, and all the emotions, the stress, the pleasure were building up to an explosive peak when "CHAAANGE PLACES!" Pinkie's voice broke the spell, leaving Twilight dazed by the sudden disappearance of those pink pillows and the chill air on her bare shaft. 

"My turn!" Dash's voice filled the sudden silence right before she crashed bodily into Twilight, knocking her backwards onto a makeshift bed of papers and uniforms. "I might not be as stretchy as Pinkie, but I'll show you what this body can do." Dash might have been a slim, kinda short girl, but she was nothing if not athletic. Her toned legs wrapped around Twilight's hips, her arms around the back of her neck, pressing her face into her shoulder, her tight abs into the base of her cock, and her small but respectable breasts right below the flare. Twilight appreciated the contact, but was still mourning the loss of Pinkie's warm hole when Dash started moving, grinding her entire body up and down Twilight's, rubbing chest to chest, sandwiching her sensitive tip between their breasts and gliding her hot wet lips up and down every part of that magnificent rod she could reach. Twilight was stunned, immobilized by the new sensations as much as Dash's grip when the rainbow mop of hair that had been nuzzling her neck moved and something hot and wet engulfed the tip of her flare. 
Any thoughts of struggling fled Twilight's head instantly, not that she had seriously considered it. That so much stimulation could come from such a simple act... She was knocked out of her reverie by Pinkie and AJ flopping down on either side of her. AJ put a finger to her lips. "Hush, sugarcube," and then replaced her finger with her own lips. Pinkie didn't let her focus on AJ's encroaching tongue, squishing her soft body up against the writhing pair and snaking a hand down to massage her sack, before shortly being joined by AJ's. They remained like that for what felt like eternity, Twilight surrounded and smothered by love and worship while she tried to hold back and prolong the moment. Inevitably though, the tides rose again, and just as she resigned herself to get very sticky, again Pinkie's voice rang out and she was left bereft.

Not for long this time, thankfully, as AJ mounted up. Straddling her thighs with Twilight's fat purple balls resting against her crotch and her shaft standing proud in front of her, a confident grin on her face as she warmed up her hands.
"Please don't make a joke about milking cows" Twilight begged, and AJ laughed. "Wasn't gonna, but just you wait. 'Ain't never got any complaints from them," and she leaned forward and wrapped both hands around Twilight's rod, fingers just barely enough to encircle her girth. She started low, stroking up and down the entire well lubricated length, putting her entire back into the motion and rocking her hips, rubbing against Twilight's balls at the same time. She really was fantastic with her hands, Twilight couldn't deny it as she started to speed up, and twist, and alternate timings, all the while grinding on her now very full sack. Precum flowed from the tip like a faucet, bubbling up and running down over AJ's hands, pooling on Twilight's stomach and in the hollow formed between her balls and AJ's thighs. AJ's hands never stilled as she leaned in an licked at the freshest cream right at the source, and when Dash and Pinkie moved up to lick at the sides she timed her strokes so that each pass would smear a fresh coating of thick pre for them to lick up. 
Twilight was very nearly out of her mind, exquisite torture bringing her to the brink and pulling her back, she was desperate to cum but almost apprehensive as she felt her release nearing. "I- I'm gonna- Pinkie I swear to Celestia if you-" 
Pinkie's peals of bright laughter were the only answer she got as she and Dash hauled AJ off of her, her hands making one last stroke up the shaft before sliding off the tip and spattering droplets of painfully-close-to-cum everywhere.
For a second the only sound was Twilight's rapid panting slowing down as her body realizes it doesn't get to cum this time either, before the relative silence was shattered by the loudest, least princess-ly expletive Twilight had uttered since ascending. Pinkie just looked innocently back over her shoulder from where she was bent over against the wall, "What? It was my turn."
Twilight knew better than to say anything in response, she just stood up, took a firm grip on her steel hard and twitching cock and marched it across the room and right up Pinkie's welcoming pussy. Ignoring the satisfied noises and cries of pleasure and occasional running commentary, Twilight focused entirely on driving her dick into Pinkie as hard and fast as her unfamiliar human body was capable of, purple hips thundering against pink ass with mighty cracks, purple hands wrapped around her chest and fingers digging into soft pink tits as she slams forward again and again, pink arms straining against the wall and shaking with each strike, she was saved from a head on collision by a pair of firm yellow breasts cushioning the impact as AJ slides in front of her. Twilight's hips don't let up at all, AJ cradling Pinkie's head to her chest as her voice starts to fail her and she drops her out loud count of orgasms. 
Dash takes the position opposite AJ, pressing herself up against Twilight's back, managing to slow her frenzied thrusting slightly and whispering in her ear. "I know she's durable, but you might be going a bit overboard here Twi," but all Twilight could respond with was "Gotta cum" through gritted teeth. Well, that's a problem Dash could solve, and she grinned at AJ before ducking out of sight. Twilight's eyes went wide and AJ just had time to brace herself before she gave her strongest thrust yet, powering her hips forward with all her strength and staying here, grinding herself against Pinkie's punished posterior as she shivered. Dash was kneeling behind her, two fingers up her tight purple ass, two in her wet purple pussy and her lips wrapped around her cute little clit, smirking as Twilight vibrated around her.
It was finally time, her balls had received the signal and cock swelled in preparation. Pinkie was caught between a cock and a hard bod, and Twilight was going to unload. The last thing she saw before her eyes rolled up in their sockets was AJ pushing Pinkie's head down to her crotch so she could put her tongue to work and then her vision went white and the whole world took a background seat to her dick. Lightning flashed through her nerves, her back tensed as her sack drew tight and her shaft gave one final twitch and gush of pre before the flood. 
Only Applejack had a real view of what happened next, and she would never forget it. That same stomach that could take a buffet's worth of food without so much as a bulge developed a ridge from crotch to chest, Twilight's cock showing through her hide, flared tip and all, pulsing in time with Twilight's convulsions. Purple muscles strained, still trying to drive deeper as she pumped load after load of thick mare cream into her friend, the bulge in her stomach going from defined to vague to subsumed as her belly swelled towards full term and then surpassed it, bouncing as both their legs gave out and they sank to the floor, still joined at the hip, still unloading more than most humans, most stallions, will make in a year with every spurt. Audible sloshing accompanied Twilight's moans as they shifted from strained to relieved, and finally to exhausted as she collapsed onto Pinkie's squishy stomach, joining her partner in sleep as her cock finishes its work, only a few more minutes of gentle unconscious thrusting and filling before it too relaxes. 
Dash and AJ roll off each other next to them, their climaxes perhaps less dramatic but tiring all the same, and curl up next to the soft and warm pair.



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A small green dog struggles to drag open the door. "Twilight! Twiiiliiight!" "TWILIGHT!?"
Bleary eyed and very sticky, but satisfied Twilight blinks in the light. "Oh right, Girls! Spike said to say hi!"