Celestia woke up as she did every day for the last two thousand years before the sun was up. It's warmth over the horizon tugging at her consciousness alerting her that it wanted to rise, snuggling into her bed she whined as the spot reserved for her lovers were oddly missing.

"For the love of me, why do I have to get up on Hearth's' Warming Day before everypony else but foals ... it's unfair," Celestia groused to her pillows as she lifted her head, only to find a note on her pillow, "Now what shenanigans are those two up to?"

Dearest Love,

We have something special planned for you, and breakfast will be involved. But only after you've passed the test. The first clue is in the palace, where we shared our first kiss together, with the pony who brought us closer together.

Much love,
Twilight and Luna

Celestia cracked a small smile at the letter and brought it up to her nose to breathe in its fragrance. Lavender with a hint of jasmine. Her smile grew wider as she trotted out to the balcony, which is outside her room, and felt the cool winter breeze play amongst her coat as she lifted the sun, signaling dawn and the official start of Hearths' Warming Day.

Celestia looked at the side of the balcony and saw a simple white box tied by a red ribbon. She opened it and saw a white, violet, and blue rose intertwined together. With a note attached to the bottom of the rose-y rope.

Before she began to read it, she felt her cheeks grow aflamed as she reminiscence the day the two most important persons of her life started their, as of then, budding romance.

It was shortly after Twilight's ascension that she had wanted to be there. As Luna rose her moon, and Celestia lowered her sun. She looked with rapt attention, as the two princesses did their celestial duties, her eyes gleaming in joy. But to some extent, in envy. After it ended, she looked at them and with a blush apparent on her cheeks. They talked about some things that had weighed upon her, for what had appeared to Celestia, a while.

"Prin - I mean Celestia ... can I ask you two something?" Twilight asked nervously. Her left forehooves nervously pawing the stone floor beneath her.

"Of course, we're all equals after all," Celestia joked. But frowned as she saw Twilight still pawing the floor

"Well ... and this is all hypothetical of course," which to Celestia and Luna's ancient ears meant that it wasn't. "If I knew a friend of mine," Of course, what Twilight meant by a ‘friend’ is actually her, with anypony with ears to hear. "That had fallen in love with both of you. And you meant the world to her ... would you two be willing to share her with each other ... or would that not be possible. Because you know?"

"Know what Twilight?" Luna said as she placed a wing over Twilight's withers, which Celestia mirrored shortly after.

"Well for starters, you’re sisters! I know that it probably means something different to immortals, but if it doesn't then that's why." Twilight blushed.

"What makes you think it meant anything different to us?" Celestia asked in confusion.

"Well, you live long enough to see any mortal lovers grow old and die eventually while you two remain behind. You both have lots of magical, political, and physical power so I doubt that any of you two could be used by others to get to the other one. Which obviously removes the political fears that might pop up.

"You both have lived together for so long that you know what the other likes and doesn't, but are still separate enough for you two to learn new things about each other, and unlike mortals. You'll, unless something extreme happens, will always have one another. That's why it'd be different. Simply because you have what a lot of other beings don't, and that's time."

Twilight froze after her explanation and seemed to freeze up, before she could fall on her old habit of apologizing profusely or bolting away. Luna stepped in, "While that's true. And would be a great basis of any relationship-"

Celestia was so shocked, that she it caused her to interrupt her sister. It wasn't on purpose, but the feelings she had developed over a thousand years of loneliness from losing the one constant in her life caused her to speak up, "Really!?"

"Yes ..." Luna responded with a sideways look. As if wondering where Celestia was taking this.

"Yes!" Celestia didn't know what took over here at that moment, and looking back. It was probably a mix of wanting to let Twilight know that she was open to the idea, and wanting to indulge in a fantasy that she was thankful that Luna, to the best of her knowledge, didn't see in her dreams.

Pulling Twilight close, she wrapped a foreleg around Luna's neck and kissed her passionately. Before then moving on to kiss Twilight. While Luna sat in shock, a stray hoof touching her lips.

From that moment everything changed. Luna gently pried Celestia off away from Twilight's lips before taking Celestia's velvet lips as her own. After a short eternity, she gave a dreamy eyed Twilight a kiss in return. From then it was a dance of partners flowing from one set of lips to another.

After the moment had passed Luna looked at her sister in a starry, wide-eyed way. As if seeing her in a new light, "While I don't object, what brought this on dear sister?"

"Twilight. Her wanting to share us, and I'll admit when you were ... away, I had missed you dearly almost every minute of everyday. And that missing you grew to fantasies of what I'd do when you returned ... which over the centuries grew into a longing I thought I'd never be allowed to have in reality.”

"But ... this," She motioned with a sweeping gesture of her wing, "This I'd like to try."

"Then dearest Twilight, it's settled. We shall be your marefriends and we shall share you with each other," Luna said nuzzling the one who brought them together in more ways than one.

Celestia shook herself from her revelry, as a warmth grew inside her chest that had nothing to do with the sun shining upon her. Looking at the note she let out a mirthful laugh.

Dearest Love,

The next clue is in the spot where we first made love. We've also left you a little snack that has plenty of warm memories.

Much love,
Twilight and Luna

Celestia spread her wings and glided to the maze. The walk to that particular spot wasn't a long one. Not with it being a place they had made love plenty of times since that first moment. And sure enough, in one of the special clearings of the maze where a gazebo sat yet another box wrapped in a red ribbon.

Opening it she saw a giant cupcake. But not just any cupcake, this was their cupcake. She grinned as she looked upon the next clue, as she munched upon the cupcake and yet again let memories sweep her up.

The cupcake came about from a source when thinking back on it should be of no surprise as Pinkie Pie. It was after their kiss the next morning when Pinkie Pie popped out of a water sprocket in the tub as they cuddled next to each other while brushing their teeth. After the initial shock, Twilight talking them out of tossing her to the nearest star that wasn't the sun for spooking them.

Asked what Pinkie Pie was doing, and with a smile that seemed to break her face. She said, "What else silly. I want to know when I can throw a "Celestia, Luna, and Twilight Finally Have Special Someponies and It's With One Another" ... or a "TwiLunEstia Couple Party"."

The royal sisters were even more surprised at the lung capacity needed to say that in one breath without sounding like she was rushing herself, before the implications of what she said sunk in. It was thankfully Celestia who could speak before the shocked, and embarrassed reaction could leave Luna in shape enough to speak.

"I'm sorry my little pony, but this is something we need to keep secret. At least for now," Celestia said with as much calmness as she could muster.

"Okay, cross my heart and hope to fly, stick a cupcake in my eye," Pinkie Pie said doing a strange ritual, that Twilight later told them was a Pinkie Promise, which was similar to an unbreakable oath, "But even if I can't throw you a party, I'm still going to make you something special."

"Why's that?" Luna finally asked after coming out of her state of shock, her toothbrush hanging out her mouth as she spoke.

"Simple silly filly," Pinkie said ignoring Luna's look of indignation, "Both you and Celestia are important ponies to Equestria, but haven't had any special someponies in like forever. And Twilight is super special to me and has never had a special somepony. So since you're all my friends, and I care about you three a lot. It's my solemn duty as your friend to make you something special for something this special."

"That ... that is very kind of you Pinkie," Luna responded with tears in her eyes. And even though Celestia would deny it, her eyes to were holding back tears from the sentiment.

"Well I got to go get things prepared. Expect something from the Cupcake Fairy tomorrow," And with a triple ariel she popped into the mirror only to keep going until she was gone in a distance that didn't exist.

"Does she do that often?" Celestia asked torn between amusement and sanity rending awe.

"You get used to it eventually. It's an aquired taste, like caviar or wine," Twilight responded to with a shrug.
And sure enough under their collective pillows the next morning, was a box from "the Cupcake Fairy", that was as big as Celestia's Cutie Mark. It was a mix of angel and devil food bread with a purple, berry flavored swirl throughout. And on the top was a light cream topping with the right side a stylized sun joined to a stylized crescent moon like Luna's Cutie Mark with a purple star behind them. All in all it was the greatest cupcake that she ever ate.

Celestia's memories wandered to that spot at the gazebo. Looking at the cushioned table sitting before her. Truthfully several centuries ago when a table that could pass for a bed, or even a reclining area came back in vogue, her garden staff had a thirty page essay on why her maze absolutely had to have one for special areas. It made her laugh so hard, and feel not the least bit prideful for their incentive that she agreed to it.

The move had made such areas quite attractive to ponies visiting Canterlot to find the areas for special gatherings. Even Rembrandt, had a few etchings inspired by a place not too dissimilar to where she sat now.

But four months ago it gained a new spot in her memories. Twilight, Luna and Celestia had been dating for several months at the time, and their physical intimacy didn't extend far beyond the many kisses they shared, or cuddling. Even their secret dalliances out to Ponyville, or even their less discrete visits for one justification or another, never blossomed more than light, love filled touches.

It was in one of Twilight's many visits to Canterlot that Luna sprung the idea for a picnic for the three of them. She had even cooked the entire meals in advance, and Celestia lovingly agreed. Warmed by her sister's romantic gesture.

It was after a beautiful lunch, while they rested in one another's mingled embrace that Luna made the first move just as Celestia did when their relationship first started.

One of her luxuriously soft indigo wings caressed Celestia's own while her tongue snaked into Twilight's passionately dancing within Twilight's mouth. Pulling back she huskily whispered, "I want to make glorious love to you two. But if you aren't ready we can wait."

Twilight answered with a kiss of her own, as her tail teasingly petting Celestia's flank. Her silky soft tail sending shivers down Celestia's spine.

Luna wrapped her mouth around Twilight's horn. Caressing her horn with tender ministrations of Luna's lips, and gentle massages of her tongue upon the shaft. Twilight's eyes went out of focus as coos flowing out of her mouth. Celestia took advantage of the moment, and bit down on the spot between Twilight's wings. Drawing in the flesh with her mouth and using her tongue to massage the knotted muscles located there. Smoothing them out with her passionate kisses, eliciting a squeal of delight from the newly-crowned princess.

As Celestia moved lower, Luna read her intentions and angled herself so that Twilight could get ample view of her plush, lustful pussy. Her clitoris winking lasciviously at Twilight drooled at the sight. Just as Twilight gave Luna a tentative lick, Celestia stood over Twilight giving Luna a full display of her own pussy as she lowered her head to Twilight's nether lips and kissed them as she would her upper ones. Her lips gracefully gliding across them.

Celestia almost pulled out as Luna dove in and caressed her clitoris with her tongue sending waves of pleasure through her. She went back to Twilight with reckless abandon spurned onward by Luna's own ministrations.

With how Luna started panting with lust filled desire into Celestia's love box. Celestia smiled as she heard Twilight squeaked happily as she went down on her sister. Drawing Twilight's clitoris into her mouth she drew her head back stretching the clit gently and played with the bulb drawing a pleasured moan from Twilight as she felt her own body start clenching from the oncoming orgasm that was threatening to crash through her.

Soon it was Celestia and Twilight who came first. With Luna responding to the orgasm vibrating through her as Twilight let loose the Royal Canterlot Orgasm deep into Luna's love box. Soon they lay cuddled around each other, panting heavily from their lovemaking.

Celestia blushed as the lips beneath her tail burned with desire, as her face blushed brightly from the memories of their first time together and the flashes of memory of the many times after. Celestia shook her head and forcefully closed her wings as she trotted over to the next location. Another place of memories, although this one was bittersweet as much as it was a happy one.

She made her way to the Royal Dining hall. It was here that their relationship came out into the light, and all of Equestria learned of the incestual pairing of the Princesses and of their shared relationship with Twilight. It was such a small thing really, and it would have been bad enough if it was a slip from the castle staff.

Rather it was a scheduling error. The three Princesses had came up with the idea of giving ponies an inside view of a Princess' day to day life. But they forgot the date, and were walked in by a swarm of elementary schoolers and journalists as they passionately kissed each other, their hooves touching some rather non-foal friendly places.
After trying and failing to will themselves to death from mortification, and damning the first amendment that Celestia formed to give more privileges, and betterment of life to the common pony. They moved they had to give the dreaded talk to the foals. While the adults ranged from as equally mortified to barely contained desire.

After many pictures were taken, and with it having been a public event, it didn't take long for their relationship to be public knowledge within the day. While the public outcry of their immorality being everything wrong with Equestria was expected. What came as a shock were the many ponies who came to their side and supported them. In hindsight it shouldn't have been as much of a shock as it was, seeing as their nation was raised in a culture of friendship and tolerance ... the later being more harder than the first.

Nonetheless, over the months, their supporters out spoke the dissenters. But with it out in the open, the world changed, although it still had yet to be seen whether it was for the best or not.

Celestia let the flow of memories settle as she noticed a tray of fruit salad and cake with a note beside it.

Dearest Love,

This is the last clue. Make sure to eat up and get your stamina up for the last part of your gift. As you can guess each clue responds to a memory that holds importance to us. But we're looking to form a new memory, just as beautiful. Come to the library, Twilight's idea, for the secret surprise and your tasty treat for being a wonderful marefriend.

Much love,
Twilight and Luna

Celestia walked into the library not knowing what to expect. But she doubted anyone could have expected a condo sized book fort in the middle of the library, with a giant cloud bed with her lovers wrapped bondage styled with their snatchs on full display.

"Before you unwrap your gift, I think I should explain the rules," Twilight said with a seductive grin.

"What rules?"

"You can only unwrap one of us at a time, and there are only two potions. The one you unwrap will join you in taking the cock-growth potion, then rut the still wrapped up one. Rule two, is we're both in estrus, so you have the honors of getting one of us pregnant first with your foal. The one who doesn't get pregnant get's to get you pregnant when you come into estrus."

"Those sound like fair rules. So my Hearth's Warming day gift is a foal?"

"Verily, and if you're a good filly, you might get a special gift afterwards," Luna breathed huskily.

"Don't tease her with that, we'll give it to her regardless," Twilight huffed.

"Posh, you know how she loves being teased," Luna replied with a wink which brought up a coughing fit from Twilight.

Celestia let loose a lusty chuckle, she knew her sister enough to know her games. And enough to know that she was moving the game for her to be the one to be unwrapped last. But she had to admit that Luna having her foal, while she carried Twilight's would be a wonderful gift indeed.

"Alright my loves. I guess that Twilight gets unwrapped first, and since you love being such a tease I doubt you'd mind if I tease you a little before filling you with my seed," Celestia teased.

That comment made a coughing fit from Luna as she was shocked to silence from the sudden turning of the tables. Her mischievous smirk faded.

Leaning down she licked the puffy lips of Luna's nether lips as her nose was filled with the strong scent of a mare in heat. Luna gave a squawk of surprise, that gave way to shuddering moans of pleasure as Celestia's tongue thrashed within her clenching walls. Celestia hummed happily from the exotic flavors of Luna's juices filling her mouth. Celestia always found it wonderful how the innate magic of ponies gave unique flavors to the bodily fluids reflecting their inner selves. But that flavor was much thicker when a filly or a mare was in heat. The rich cocktail of hormones with magic pulling to the womb to ready the body for a foal.

As she pulled back she said, "So my delicious lover, what is the secret you to have planned?"

"Never!" Luna moaned.

"Never?" Celestia asked as she sent a tendril of magic to Luna's G-Spot and vibrated it mightily, making Luna scream in ecstasy.

Just as Luna's screams she turned to the beginnings of a confession to appease Celestia, Celestia received a pillow to the face. "No cheating Celestia!" Twilight huffed, "and aren't you forgetting some pony?"

Celestia blushed, "Sorry love. I guess I got carried away."

"Well unwrap me and play fair, then I might forgive you," Twilight replied pouting.

Walking over to Twilight Celestia replied, "You look so adorably sexy when you pout like that. But before I unwrap you, let me make it up to you," as she aimed her pussy over the quivering tip of Twilight's horn.

Celestia slid off of Twilight's horn a mixture of ectoplasm and mare juice dripping down Twilight's face. Celestia undid Twilight's bindings with her magic while angling her so that she and Luna could clean Twilight's face with their tongues.

After they had cleaned up Twilight, Celestia whispered, "So am I forgiven?"

"Uh-huh! Definitely!" Twilight sighed happily.

Twilight stumbled over to Luna and Celestia rushed to hold up Twilight, "Are you alright?"

"Don't worry, it's just sex legs. I'll get my legs back eventually," Twilight brushed Celestia's concern with a playful brush of her wing.

With a nod, they chugged the potions with Celestia positioning to Luna's snatch, and Twilight positioned before Luna's face.

Celestia chuckled, "I think you hornfucking me got Luna wetter than me hitting her spot. Isn't that right you dirty little filly?"

"Yes! Give me what a dirty filly like me deserves! Punish me!" Luna shouted.

"I'm so glad I reserved the library to ourselves today," Twilight hummed as her moderately sized mare cock grew from between her legs.

"I am too, so how are we going to do this Twilight?" Celestia asked.

"Easy we use our magic to lift her and then you pull her to you to hilt yourself into her pussy. Then when you push her to me she gets a mouthful of mare cock. She can break the bonds easy and if she does that's our sign to stop."

"Alright, then I guess it's time."

It had been awhile since she had wielded the beast that was her cock, but as she slid her meaty member into Luna's greedy snatch, squeezing her cock. She remembered how fun it was to play with a cock. Luna's moans were muffled by Twilight's cock in her mouth.

As they continued, the slick, juicy, luscious walls of Luna's pussy drove Celestia mad with need. But she could feel her coming to bursting. "I'm going to cum in you Luna!" Celestia screamed in the Royal Canterlot Voice. The book fort condo rattled and shook.

Luna tried responding but the cock in her mouth received the full vibration causing Twilight to squeal as she came so hard that her spunk shot out of Luna's nose and she passed out from the force of her porngasm. With Celestia's cum shooting right after. With several centuries of blue balls worth of cum shooting into Luna's womb with the force strong enough to shoot Luna off of her cock and onto the resting form of Twilight Sparkle.

After a cleanup spell, and waking up her lovers. She unwrapped up Luna, and nuzzled both of her special ponies lovingly.

Twilight and Luna looked at Celestia and they looked at each other and nodded.

Twilight said, "So as you can guess, starting a family between the three of us was part of the first part of a beautiful memory."

"But that isn't the main part of your Hearth's Warming gift."

"So now that you've enjoyed the first part of your gift."

"Celestia-"

"Our love-"

"You are the most important pony in our lives -"

"So Tia -"

"Will you marry us?" They both finished.

Author's Note

Sorry for not indenting. To much to do atm. I started at noon, and I wanted to give all of my readers a nice little gift. Although I'm still rusty on menage'a toi's. But while it's not foalcon, I still think this is a fluffy fic. I hope you all enjoyed it, and have a very happy Hearths' Warming.