Twilight didn't know what to expect. She had seen the portals before and seen… well, ponies through them. As she opened her eyes she was looking right at one. "Uh, hi?"

"Welcome to Equestria. Watch your step, it will probably feel a little odd with four legs, I guess." Gel tried to get the unicorn that looked so like his wife away from the portal before-

"Ugh, hey!" Sunset had landed and fallen into the first pony. She tried to get out of the way of the portal, using her magic to lift Twilight up and away as well. "Gel?"

The changeling nodded. "I owe Twilight twenty bits. Welcome back to Equestria, Your Highness." Gel gave a slight bow at the now very confused Sunset.

A blue pony stumbled from the portal and trotted away from it, turning to glare back, her wings spread. "I said I would go though, they didn't have to… oh wow!" The pegasus' eyes widened as she took in the three ponies already before her. "This is so awesome!" She raised a forehoof and her wings.

"Told you it would be." Sunset was still a little shaken, particularly when she did a little self-check and her brain was coming up with two limbs more than it should.

Rarity was next, stepping out of the portal and immediately squealing in terror. She rushed over and hid behind Twilight. "Why am I naked? Why is everyone else naked?" This had the unfortunate effect of making the other two girls, new to being ponies, examine themselves.

"Well, clothes would look a little silly on a pony." Rainbow Dash just shrugged, but poor Twilight was having a worse reaction than Rarity.

"W-W-W-Where are my clothes? I can't be seen like… like…" Twilight's eyes turned to Gel, realizing there was a male in the room with her while she was naked. It was worse than the pods.

Pinkie Pie was next, appearing with a giggle and bouncing around the room before she had even worked out how to walk. "Oh wow, this is great. We need to throw a welcome party."

Applejack was soon followed by Fluttershy, both looking a little shocked at the lack of clothes, but oddly, Applejack handled it better than most. When Princess Twilight returned to Equestria, there were a lot more gasps as the others turned to her. "What?" She almost recoiled.

"Twilight! You're pregnant?" Rarity rushed over, her nudity taboo forgotten for a moment. Her head spun and settled on Gel. "Really, is he the stallion who got you this way?"

"Only half way." Twilight blushed and looked for her husband, finding him helping Sunset cope with the realization that she was an alicorn. "Oh boy, I want it by tomorrow, Gel! I won the bet!"

"There was a bet on me being an alicorn?" Sunset looked shocked a moment, then giggled. "Okay, fair enough, I can see that. So what does this mean?"

A unicorn head poked in the stairs leading up to the castle itself. "Are your friends here ye-" Starry saw all the ponies, giggled and bolted back up the stairs.

"What is going on here?" Rainbow Dash was distracted from playing with her wings by the short-term visitor. "Who was that?"

"That was Starry, she is our friend who lives here as well." Gel pointed with a hoof. "Want to head upstairs and we can find rooms for everypony so you can get settled?"

"What about clothes?" Rarity stomped a hoof in indignation, hiding behind Sunset. Fluttershy was quiet but no less determined not be seen naked, as was Twilight.

"Well, your cases made it over fine, maybe they are now pony clothes?" Pinkie pointed to the suitcases and Rarity was on them like a shot. She fumbled with her hooves for almost a minute while everypony else watched before she gave a whine.

"How do you use these things?" Rarity shook her hooves in the air in despair. "They are useless!"

Princess Twilight lit her horn and popped the clasps on the first case. "You have magic, Rarity." She further demonstrated by opening the case. "Just think of what you want moved and how, then push at it."

Glaring at her hooves one last time, Rarity turned her attention to her case. She stared at it, thinking of how she would just need to squeeze on the little latches and… she jumped in shock when the latches glowed blue a moment and unlocked. "I… I… was that me?"

"Sure was!" Princess Twilight gave the unicorn a hug in celebration. "Unicorns are a natural for magic, to use it like that is the same as walking. Perfectly natural." Rarity wasn't listening, however, she was going through the cases and pulled out one outfit.

"Darling, you can wear this one, it suits you better." Rarity floated the first dress toward Twilight, the unicorn blinking and barely catching it with her own magic.

Twilight's eyes were wide. This was real magic. "This is real magic…" She held up the dress, turned it and then dropped it, looking around for something.

Knowing just what her alter-ego would need, Princess Twilight made a scroll and quill appear. "Here you go, I will have to teach you that spell quickly, I bet you are going to be writing a lot."

Seeing her friend already distracted writing, Rarity collected the dropped dress and hung it over Twilight's back. "Really now, Twilight Sparkle, you sure you don't want a dress?"

"Huh?" Twilight looked up from her scroll, she was writing about writing with magic and quill. It was a start. "What do you…" She quickly grabbed the dress with her magic and, faster than Princess Twilight had ever been able to dress herself, was in it and covered. The scroll and quill were taken up again.

Pinkie Pie had managed to slip away while the rest were all distracted and clopped her way up the stone stairs and poked her head out up the top of them. Her jaw fell open. "Sunset said she had a castle but-"

"Surprise!" Pinkie Pie and half a dozen other ponies bounced out from behind various things, making the new mare jump almost to the ceiling. "Aww, where are the others? Oh, wait, you're me!"

The two pink ponies were standing, almost nose to nose. Both giggled at the same time. "We have to surprise them together!" Their voices matched perfectly and both lifted a hoof up to bump together. The Mirror Pinkie giggled, she didn't even know why she made the gesture but it felt right.

Hearing a sound from the stairs, both Pinkies raced into cover, hiding together and giggling at each other.

Waiting, seeing Mirror Rainbow Dash leading the way, both mares giggled a little. It wasn't until all the ponies were out of the castle basement that they both jumped out. "Surprise!"

The confetti and glitter was so thick it was impossible to see the intended targets. Stories would be told of the double party-cannon blast for years to come.

"Pinkie!" Mirror Twilight couldn't see the paper in front of her anymore, but she knew of only one girl who would be able to make this much mess so quickly. "What in the name-" She broke off, seeing two pink ponies that looked like her friend. "There's two of you?"

"Yup!" Both Pinkies said at once, giggling themselves silly. Only one of them continued talking. "But that me is your friend-me. This is the pony-me. When Twilight-me…" Pinkie froze for a moment, having confused even herself. Starting again seemed like a good idea. "When Twilight told me you were all coming over for a holiday, I just had to throw you a Welcome to Ponyville party!"

"It is! Oh, we could hold a party to welcome Ponyville to us!" Mirror Pinkie was bouncing in excitement, soon to be joined by regular Pinkie.

"Well howdy partner." Applejack looked at her clone, noting the other mare even had a duplicate of her hat. "Welcome to Ponyville." She smiled widely and got a smile back from Mirror Applejack.

"Shucks, glad to meetcha." Mirror Applejack held out a hoof, getting it clopped by her twin. "This really a castle?"

"You betcha, Twilight is a princess in all senses of the word. Princess of Friendship." AJ was talking about one of her favorite topics so was more than a little chatty. She sighed happily when Gel came up beside her, leaning in to nuzzle and kiss her cheek.

Mirror Applejack blushed and quickly looked around, spotting Princess Twilight watching them. Her blush increased and she expected all hell to come down in a moment. But the princess wasn't storming over to confront her husband. "Okay, somethin' ain't right here. I thought the Princess said you were her husband?" She pointed a hoof at Gel.

"She did and I am." Gel nodded and leaned up to Applejack's ear. "Five bits says we need to explain it to her." His whisper got a grunt from his orange wife.

"Gel, Ah swear, ever since that race you been wantin' ta gamble on anythin'!" Applejack rebuffed his wager. "Look, uh, Applejack. We kinda got a… uh… well, we are all married."

Mirror Applejack's jaw opened and closed a few times. It took her a moment and she looked around the room at all the mares present. "What, all'a y’all?"

Applejack shook her head. "Twilight, Gel, and myself." She reached up and put a leg over the stallion's withers, pulling him in for a hug.

There were six pairs of eyes blinking in surprise. Mirror Pinkie Pie was missing, absconded with regular Pinkie Pie.

"So, are we going to plan the party? I bet there is a lot of stuff we need to-" Mirror Pinkie was in full-plan mode but was cut off by a hoof against her mouth. "Mfmfm?"

"Silly, I wanted to ask if you wanted a special party? And to… to see if you liked the same things I do…" Pinkie Pie pulled her hoof free.

"Special party?" Mirror Pinkie looked split between even more excited and intrigued. "And of course we like the same things, we are the same person… pony!" She froze, however, when she felt a hoof gently trace down her side and circle around on her thigh. "Oh… special… party…" She turned her eyes up to meet her twin's own and didn't hesitate in kissing herself.

Both ponies broke the kiss in a giggle. "Did you just-" Both froze as they were talking at once. "I felt like it and-" They stopped again. Each made to talk again but stopped, testing the other to see if they would break. They giggled and kissed again, each closing their eyes and melting into the kiss.

Finally, needing air, Mirror Pinkie gave a happy gasp. "Where are we?" She looked around as the other pony stroked her flank and a bit further back.

"This is one of the castle's guest rooms. Don't worry, nopony will come in here." Pinkie brushed down her twin's plot, giggling and watching the other mare lift her tail. "So you want to have a special party?" Her answer was another kiss as she was pounced and tackled to the bed.

Mirror Pinkie looked down at herself, well, her other self. "Ponies look a little strange. No breasts?" She ran a hoof down Pinkie's barrel, noting that there weren't even nipples.

"What are you looking for?" Pinkie liked what she saw as she gazed up at her inquisitive self. "You have bits up there? Doesn't that get in the way of-"

"No, silly. We have breasts. Uh…" Mirror Pinkie stroked the soft pink fur while she thought. "Oh, what your children feed from, make milk!"

Pinkie grinned wider and wider. "Lay down on your side and let me get down to business." She rolled herself over so it would be easier for her other self. When she saw pink belly-fur, she started. "Okay, lesson one in fun things to do with a mare." Pinkie leaned in and nibbled gently around her twin's udder, getting a happy moan from the mare. "You like? Now you try."

Groaning a little more, Mirror Pinkie watched as her twin's leg lifted, showing off her playground. "Oh, like a cow?" She leaned in and nuzzled around the udder, using a gentle hoof to rub while she latched onto a teat and sucked.

"Oh… yeah… right… right there." Pinkie nuzzled and licked, nibbled and toyed with her new best friend. When the other mare finally went further and she felt a long, broad tongue slip down her slit she followed suit and the party was on for real. Knowing how sensitive her own little button was, Pinkie Pie focused her attention on her twin's clit, getting startled whimpers and moans.

Mirror Pinkie was stunned by the pleasure at first, her body giving a little buck as she was being played with. But this wasn't just her party, this was a special party for both of them. Feeling the naughty mare's lips on her clit one more time, Mirror Pinkie licked and started to suck on Pinkie's, getting whimpers and squirms as her reward.

The pair hit their peaks at the same time, exactly the same time. Both moaned happily into each-others vulva, their noises muffled by soft, pliant flesh. Panting after the orgasm, each was lost for words a moment as little aftershocks crackled in their nerves. Mirror Pinkie recovered fully first, but as she started licking and nuzzling again, her native twin's reply was limited to happy sounds and returned nuzzles.

A special party indeed.

Author's Note

Does that count as masturbation? Incest? Twincest? I am confused!

Also, anypony who was betting on Pinkie Pie losing her Equestria-cherry first wins a hug from Shining!

Oh, and apparently, the rum is gone.

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