“Sit down there at the edge of the bed, Sister. I believe Twilight and I may be able to speed your recovery...” As Luna said it, she nudged Celestia forward with a none-too-gentle nuzzle against her backside, following it up with a playful nip.

Twilight smiled at the sudden jolt that visibly ran through Celestia's body at the pinch of her sister's teeth on her ass. Celestia trotted over to her massive bed with a springy, showy gait ... and also a reproachful look back over her shoulder.

Luna, though, seemed unrepentant, her eyes holding only a deep hunger for her sister. Literally taking Twilight under her wing, she followed Celestia to the bed, bringing Twilight along with her. “Come with me, Twilight Sparkle,” she said in a tiny whisper, “and you will have another chance to employ your throat. I believe you will find success far more easily when she is flaccid. 'Tis how I first learned the skill.”

Twilight bit her lip slightly. Oh, if only her younger, more panic-prone self could see her now ... about to get a lesson in fellatio from Princess Luna herself. And the subject of that lesson...

When Celestia turned around and settled down onto the edge of the bed, spreading her hind legs out in front of her, Twilight's breath caught in her throat. Even with her thick pink cock drooping down in front of her balls, the sight of that incredible package – Princess Celestia's package! – was almost like the feeling of awe she'd gotten the very first time she'd seen Celestia raise the sun. Only ... instead of making her mouth go dry, it made her mouth water nearly to the point of drooling; instead of making her stand in stunned awe, it drew her inevitably nearer.

Celestia smiled down on her as she approached. “Oh Twilight... I never could have imagined I'd see— Oh! Oh my...”

Whatever Celestia's warm sentiments would have been, they were lost to time as Twilight eagerly caught the drooping tip of her former mentor's cock on her tongue, then let it slide right up into her mouth. The taste of Celestia's leftover cum filled her mouth, accompanied by the tangy aftertaste of Luna's nectar still coating it. She looked up into Celestia's eyes, letting the love flow between the two of them as she began swallowing down that soft pink length.

And swallowing was exactly the right word. Though still heavy and warm against her tongue, Celestia's cock was no longer firm enough to simply plunge her head down against. Doing so would only have bent it. Instead, Twilight had to actively suck her former mentor's cock, beginning to make big gulping swallowing motions as soon as she felt the soft warm tip against her throat.

With every gulp, she managed to pull it deeper, packing her throat full of Celestia's soft, warm girth. And this time, there was no struggle, no choking and gagging. It felt almost like she was drinking it down, except that it filled her so completely and stayed right where it was.

Celestia reached down and ran her hoof over Twilight's cheek, following the side strap of the lace halter. “Oh Twilight, you're so ... so... Mmm...”

Finally, Twilight's lips kissed against Celestia's sheath, but that hadn't been the only thing that prompted Celestia's moan. Luna had nudged her way in beside Twilight and taken her own place down at Celestia's massive pink balls, gliding her tongue over their huge curves and nuzzling her way into every musky crevice she could find.

At the feeling of her sister's tongue in so delicate a place, Celestia let out a long, shuddering breath. Her cock grew firmer inside Twilight's throat, filling her to the point of discomfort, but Twilight forced herself to keep going, to keep bobbing her head up and down slightly in her former mentor's lap, to keep slathering her tongue over that thick and veiny base of Celestia's cock, to keep swallowing – massaging Celestia's length with her pulsating throat, even as her unchecked drool began dripping down around Celestia's sheath. Twilight's pussy – so recently and utterly satisfied – awoke and winked again, dripping a bit more of Luna's cum onto the floor behind her and making her tail rise involuntarily.

Celestia glanced upward a little, obviously noticing that upward twitch. “Oh Twilight...” Her cock stiffened even more, forcing Twilight to change the angle of her neck to accommodate it.

But Twilight was committed now. Her only response was to push herself down harder, rocking back and forth a little as she plunged down again and again onto Celestia's cock, pushing as if she meant to swallow even that thick pink sheath as well. Shifting a little to stand on only one front hoof, she brought the other up and used the soft, supple fabric of her stocking to caress Celestia's hefty balls, tracing around their bulging curves and holding them up against Luna's eager face. For a moment, she lost focus on her ultimate goal for the night. The fantasy of Celestia cumming down her throat, emptying those huge balls straight down into her as she drank down every drop of the thick cream ... it overwhelmed her, made her plunge her head down onto Celestia's ever-stiffening cock even more fiercely.

As Celestia's cock became completely hard, though, that fantasy broke down. Twilight's already-strained throat met its limit. She coughed uncontrollably, and a sputter of her own spit burst out around her lips, splashing up onto her own muzzle and dripping down onto Luna's face below. As another gagging cough rocked through her, she pulled her head up. Celestia's length slid solidly against the inside of her throat, all the way out, until her pink tip, dripping with bubbly spit and pre-cum, popped free from Twilight’s mouth.

For a long moment, Twilight simply stood, staring at that wonderful cock as she sputtered for breath, making up for the lack of air she'd been forcing on herself so recently. Without thinking about it, she wiped her sodden mouth with one forehoof, only thinking of the delicate fabric of the stocking after she felt its silky softness soaking up her cum-laden spit. She glanced up at Celestia and felt her cheeks heating. She'd failed. Luna was better at sucking cock than she was. Far better.

Even now, Luna was still as dedicated as ever, tenderly licking and sloppily kissing every last little bit of Celestia's bulging balls, even going so far as to press her cheek hard against Celestia's inner thigh so that she could tuck her muzzle up into the steamy little gap between white thigh and pale pink sack. And down under Luna's own belly, her dark blue cock was beginning to rise again.

But when Celestia looked back down at Twilight, she looked anything but disappointed. Perhaps it wasn't the look of admiration Twilight had been hoping for, but it was something better: a look of utter adoration, ready to give herself fully to her former student.

Twilight licked her wet lips slightly. “Um, is it okay if I... I mean, are you ready to...?”

Beckoning Twilight closer with a twitch of one forehoof, Celestia smiled down at her. “I am ready,” she said in a whisper barely louder than Luna's slurping sounds from below. “I want you more than I've ever wanted anyone before.”

Ignoring the indignant little sound Luna made in response to that, Twilight went to Celestia.

She carefully stepped over and around Luna, bracing herself up on Celestia's outspread thighs. Celestia's wet cock rubbed down over her chest as she climbed, and she leaned into it, sliding over her former mentor's length, letting it rub its way down her swollen belly, past the tightly stretched girth strap of her decorative saddle, down over the delicate sensitive skin of her teats. And all the while, her face drew closer and deliciously closer to Celestia's. Just at the moment their noses bumped together, Celestia's tip rose up between her cum-soaked thighs from behind. It seemed to find the perfect place so naturally and easily, despite the unorthodox position. Right away, Twilight felt its firm heat against her sloppily winking pussy lips.

For a long moment, the two of them stayed right where they were, their muzzles touching and gazing straight into each other's adoring eyes.

“I love you,” Twilight mouthed, almost silent, barely daring to put any breath behind it.

Celestia kissed her, their lips meeting in a soft, loving warmth that Twilight had only ever dreamed of. Had Celestia heard what she said? The heat of her lips, the gentle caress of her tongue as she parted them, and the slight moan she let out seemed to be the only answer Twilight would get for now.

And Twilight would have been absolutely satisfied with that answer ... but there was more to come. As the two of them kissed, drifting off into a dreamy appreciation of each other, Celestia wrapped her forehooves around Twilight's back. One came up high, stroking the base of her mane ... and the other went down low, tracing down the groove of her spine and along the hollow of her back just above her ass.

Then Celestia gently pushed Twilight downward.

Twilight couldn't help feeling it was like the warm sun coming out from behind a cloud. She basked in the feeling of Celestia's warm cock parting her already-filled pussy open again, flowing up into her, filling her. Aided by every kind of unspeakable slickness, her shaft glided perfectly against Twilight's inner walls. Twilight smoothly and slowly sank down onto it, taking Celestia's entire length in one gloriously gentle stroke, all the way down until her outspread ass cheeks came to rest against Celestia's thighs, Luna's starry mane tickling the dock of her pertly raised tail from underneath. And through that whole time, their tender kiss never broke. She never lost the touch of Celestia's warm, soft lips.

Not until Celestia broke the kiss, at least. She slid her cheek along Twilight's, even as she held their bodies tightly together. When her muzzle came up next to Twilight's ear, she whispered even more quietly, “I love you too, Twilight.”

With a sudden gasp, Twilight lost it. She nearly orgasmed again on the spot. And Celestia must have felt the urgent squeeze from Twilight's pussy, because she answered it with a twitch of her cock inside.

“Are you ready?” Celestia asked in a more normal voice – but still tinged with unfathomable depths of love.

Twilight wrapped her hooves around the back of Celestia's neck, burying her face in that marvelously flowing mane. “Yes!” she breathed out desperately. “I want it – I want your foals!”

Celestia stroked the back of Twilight's mane tenderly. And slowly, ever so gently, she used her other hoof to begin rocking Twilight's hips back and forth in her lap.

As their close, intimate motions gradually intensified, Luna grew bolder down below. Now not only did she lovingly tend to her sister's enormous balls, she also ventured upward from time to time, teasing Celestia's sheath ... even licking along the edges of Twilight's pussy lips where they stretched out perfectly round to accommodate Celestia's girth. She must have been licking up remnants of her own cum as she did so, but that didn't seem to hold her back in the slightest.

Twilight's pussy winked uncontrollably. She began rocking her hips all on her own – pushing forward and back, forward and back, desperate to feel Celestia's cock moving inside her more and more. The length of Celestia's cock seemed to touch everywhere inside her, and everywhere it touched it left a warm, tingling glow.

Celestia's hoof held her tightly along the curve of her lower back at first, but began drifting lower, following the garter straps down from the back of her saddle around to the curve of her ass. Twilight gasped a little when the crook of Celestia's hoof grabbed around her cheek, squeezing its roundness. She rocked herself even faster then on Celestia's lap, feeling herself quickly building toward another climax, just from the idea of how much Celestia was enjoying her. And as she moved, Celestia's cock twitched and pulsed inside her, showing her in the most intimate way possible just how turned on her former mentor was getting.

But Celestia wasn't the only one with a growing arousal. After a moment's absence from below, Luna came up behind Twilight, rearing up behind her and sliding her way up Twilight's back. “May I, Sister?” she asked with every hint of formal politeness.

Celestia looked up over Twilight's shoulder at her sister with an indulgent grin. “Oh certainly. Please do.” She lifted Twilight up a little bit, pulling the smaller purple pony up off of her cock.

Twilight whimpered as that big, beautiful and warm cock left her gaping ... but only for a moment. Because that awful emptiness was filled a scant moment later with the heat of Luna's cock instead. Shuddering, Twilight sank down onto the other alicorn's cock, her eyes losing focus a little as she was once again massaged from the inside out by Luna's sensuous shaft.

Luna, gracious as she was, only kept her for the space of a couple heavy thrusts before lifting her up again, passing Twilight back to Celestia.

This time, Twilight didn't make the slightest sound of complaint when she found herself empty for a moment. Now she knew this for what it was. The sweet sense of anticipation more than made up for the momentary lack of warmth and fullness. And not only the anticipation, the fulfillment of it. Twilight felt as if she could melt as Celestia's cock reentered her. So slickly, so easily. Celestia pushed all the way into her in one effortless thrust.

For a time, Twilight lost herself in the sensuous embrace of these two sisters. Everywhere she looked, everywhere she touched, everything that touched her ... all of it was nothing but two of the ponies she most adored in the whole world. Every time they passed her back and forth between each other, she yearned to feel that other cock inside of her. Every time they pressed her tightly between each other, she felt as if she was the conduit for their sisterly love to flow through. Every time they kissed her, from in front and from behind, she felt like she was the luckiest, most enviable pony in the world. Both of the other alicorns breathed heavily into her mane, one from either side. She could swear that their oversized balls must be bumping into each other's down below her own body. She wished this would never end ... and yet at the same time she couldn’t help longing for the moment when it would all be fulfilled, when Celestia and Luna came again, filling her to the brim with their extra-potent seed.

And it seemed that moment might be coming... This time, after Celestia had taken her few passionate thrusts, she didn't lift Twilight up and give her back to Luna. Instead, she clutched Twilight even tighter, her breath burning against Twilight's neck as she slammed Twilight down again and again onto her ragingly hard cock.

“Sister?” Luna asked, her cock rubbing up and down between Twilight's ass cheeks.

“Too ... close!” Celestia grunted between desperate breaths. Before either of the others could react, she twisted around, taking Twilight with her and turning them both away from Luna.

Twilight mewled helplessly as Celestia pressed her belly-up against the bed, still thrusting into her but taking total control now. Giving herself up to it, Twilight arched her back against the soft golden bedsheets, giving Celestia a perfect angle to push into her again and again, harder and harder. Celestia braced her hooves on the bed to either side of Twilight's body, squeezing her in between them, holding her perfectly in place as she went in for a fully feral rutting, using Twilight's willing pussy to its fullest extent.

But Luna wasn't to be denied so easily ... and Celestia's change in position left her at a certain disadvantage from behind.

At first, Twilight didn't see Luna coming up behind her sister. She was to focused on staring up into Celestia's needy, desperate eyes. But then the look on Celestia's face changed – changed drastically. Her mouth suddenly opened into a silent 'o', and her eyes shot open wide. “Luna!” she said, her voice uncharacteristically squeaking.

“Yes, Sister?” Luna said, her face appearing above Celestia's shoulder as she slid into place over her back. She gave one solid thrust, which in turn pushed Celestia's cock into Twilight.

As Luna worked inside her sister's pussy, Celestia gradually bent down lower ... within kissing range. Twilight eagerly lifted her upper body just a bit, closing the last bit of distance and kissing her former mentor as lewdly as she could manage. Being filled with Celestia's warm cock was one thing, but this ... this was even better. Celestia's breaths came in little gasps, each one with a tiny little moan at the end as Luna plunged into her pussy.

Twilight ran her stocking-clad hoof through the fur on Celestia's neck, watching it stand on end as the ever-regal alicorn lost all semblance of control. Celestia moaned freely now, her breath shuddering loudly into the sheets right next to Twilight’s ear. Twilight held her close, even as she felt a little hint of drool next to her cheek. Her own insides tingled and burned around Celestia's flaring cock, even as she held the adorably overwhelmed alicorn close and tenderly. And there was only one thing that could douse that fire inside her...

“Do it,” Twilight whispered into Celestia's ear. “Cum for me. Cum for Luna. Please ... we want it... We want you so much. We want—”

With a loud gasp, Celestia came. Her cock throbbed and spewed a seemingly endless stream of hot cum into Twilight's deepest recesses. There was no more need to tell Celestia what she wanted – it was pouring into her in surge after gloriously overwhelming surge, filling her already overstuffed womb past all reason.

Either the pulsing of Celestia's pussy or just the endearingly lewd sounds she made must have driven Luna over the edge as well, because Luna followed her sister into orgasm moments later. Twilight's only clues to know this were the way Luna's hooves clutched around her sister's body and the rhythmic gasps Celestia made – not in sync with the throbs of her own cock, but timed in accordance to Luna's bursts of cum inside her.

Twilight's body swelled all over again as Celestia pumped her full with another absurdly oversized load. Her underbelly swelled against Celestia's, both of them growing as they were pumped full and overfull. Just as the excess began to seep out around the base of Celestia's cock, Twilight was filled to the point where the girth strap of her saddle snapped, either end of it slapping down onto the bedsheets now that it could no longer accommodate Twilight's expanding size.

It seemed as if it would never end, as if Celestia would keep pumping into her forever ... Twilight wanted it to go on forever. Just a bit more ... just a bit more...

Just as Celestia's orgasm first began to fade, Twilight's hit her full force, all the more powerful for having been delayed. She fell limp against the bed behind her, but only for a brief moment. Her legs might have been incapable of movement, but her body ... her body danced around Celestia's still-throbbing cock. Her swollen belly heaved up and down as her pussy clenched and milked Celestia's cock from the inside. It seemed like every muscle in her was working hard to get out every last drop Celestia's pale pink cock might be able to pour into her, even if she couldn’t possibly contain it all.

Maybe she even passed out for a short moment ... or maybe it was just a long, very dizzy blink of her eyes. Because when she opened her eyes again, Celestia was still there on top of her, still inside her, looking down at her lovingly. Luna looked down over her shoulder, gazing down with a heady mix of adoration and pride.

Slowly, obviously weary from her exertions, Celestia slid one hoof down along the bed until she reached the obscene mass of Twilight's swollen belly. She traced her hoof up and down the gigantic curve of it. Then she raised her hoof a little and touched her own belly, still enlarged, though not nearly to the extent twilight's had grown. “Oh Twilight...” She took a deep breath, and her cock pumped out its last few drops deep inside. “Thank you. Thank you so much.”

“Thank Luna,” Twilight said, looking up at Luna's face instead. She smiled as she saw – for the first time she could remember – Luna actually blushing.

“Yes...” Celestia gasped a little as Luna slid off her back, pulling out and releasing a small deluge of white to trail down her already white hind legs. “Yes, but it was you who brought this idea to us, Twilight. It was you who brought us together.” She spared a moment to lean down and kiss Twilight's forehead just below her horn before pulling out herself. “Thank you, Twilight. We should have done this ages ago.”

As Celestia pulled out, Twilight lifted her head to look up over the big purple hill of her inflated belly, hoping for one last look at Celestia's magnificent cock and those big pink balls that had just filled her to the brim. She did get one brief glimpse as the excess cum drained out to soak her tail ... but it was truly a last look, because both cock and balls promptly vanished after Celestia pulled out, shimmering into some other plane of existence in the way only magical constructs could, leaving one vaguely wondering if they were ever really there in the first place. Now the only things disturbing the long, supple curve of Celestia's belly were her pert little teats – tiny and pink and entirely ordinary for a mare like her.

As Celestia slid off of Twilight, Luna collapsed onto the bed right next to her. Celestia followed a moment later. Twilight stayed right where she was between the two, lying belly-up. She wasn't even sure she could move, not with her belly like this. Both of the sisters had swollen out until they looked several months pregnant, but Twilight ... Twilight looked like she was overdue for an entire brood. All that churning cum inside her... Had it...?

Twilight's dreamily blinking eyes shot open wide. Had it worked? Was she pregnant?

Even as Celestia and Luna cuddled up on either side of her, Twilight used her magic to pull one of the three pregnancy test crystals over to herself.

That got the other alicorns' attention when they saw it hovering over Twilight’s belly.

“Do you suppose it worked?” Luna asked breathlessly.

Celestia ran one hoof up and down the enormous curve of Twilight's belly. “Oh yes. I have every confidence that our Twilight is about to be a proud new mother.”

Twilight herself, though, was feeling far from sure. She hovered the clear crystal just above her belly, almost afraid to find out. If it turned blue, that would mean her new foal was to be a colt. Pink, a filly. And – the part she dreaded the most – if it turned opaque white, that would mean she was not pregnant at all.

Then again ... if she wasn't pregnant, if by some horrible happenstance it hadn't worked despite all the potions they'd used, well ... they'd probably just try again, wouldn't they? And that had an allure of its own ... or at least it would after she'd had a few weeks to recover from this attempt. With that silver lining in mind, she slowly lowered the crystal down onto her belly, until the pointed tip of it touched.

It flashed, shattered! The little crystal exploded, making all three ponies flinch as shards of it zinged off in two different directions.

Twilight stared at where the crystal had been in gape-mouthed horror. “W-what does that mean? It's not supposed to do that! Should I get one of the backup crystals?”

“No, no... That won't be necessary.” Celestia held up one half of the crystal that had landed on the bed near her. The jagged shard had turned a deep and very prominent blue.

Luna held up the other. It had turned a vivid pink.

Twilight stared up at the two shards as they hovered up above the bed in front of her ... no longer in horror, but still trembling a little. “What does it mean? The pregnancy test enchantment is simple. I cast it myself. This isn't supposed to happen!”

“It did exactly what it was supposed to do,” Luna said. “I invented that enchantment. The crystal split into two shards. That means you are pregnant with two foals. Judging from the colors, one filly and one colt.”

Her eyes going wide, Twilight took the shards into her own magic, drawing them close and then holding them against her chest with her hooves. Two foals? This was more than she'd ever dreamed of. “Oh thank you!” she breathed, at first unsure who she was thanking ... but then she glanced to the magnificent ponies on either side of her on the bed. “Thank you both so much!”

Celestia smiled. “Well, I suppose we won't be needing those backup crystals after all... Congratulations, Twilight. I can't wait to meet your beautiful foals.”

“Actually, Sister...” Luna used her magic to levitate over the other two crystals. She held one over herself and one over Celestia's belly. “I believe it would be prudent of us to make use of the remaining two crystals ourselves...”

“Oh...” Celestia looked down and rubbed the still-swollen curve of her own underbelly. “You're right. You don't suppose ... perhaps...?”

“I would not venture to suppose anything before putting this to the test,” Luna said. Without any further delay, she pressed the point of the crystal lightly against Celestia's belly.

It immediately turned pink. Twilight and Luna gasped, but Celestia only looked to her sister and eagerly said, “Yours next! Do yours!”

Slowly, much more reluctantly than she'd done with her sister's crystal, Luna lowered the last remaining crystal to her own belly. It instantly turned deepest blue, matching the color of her own fur almost perfectly.

“Oh...” Celestia gulped. “Oh my...”

“Indeed,” Luna said, her voice grave. “This is a ... rather unforeseen development.”

“What are we going to tell the nobles? Who's going to take care of our duties while we're busy being mothers? What about our—?”

Twilight pulled Celestia in close to cuddle against her before she could work herself into any more of a panic. By the time she got her hoof around and underneath Luna to pull her close as well, Luna was already on her way and nuzzling herself up against Twilight’s neck.

“I couldn't be happier,” Twilight said, stroking them both comfortingly with her hooves. “My new little foals will have a brother and sister to play with, and I'm happy they'll have an even bigger family. We'll all have a bigger family now. We're all in this together, and I wouldn't have it any other way.”

That seemed to content the two sisters, at least for now. They snuggled up against either side of her, all three swollen bellies pressed up against each other as they held each other close with their hooves.

Soon – very soon – Twilight would need to get up, salvage what she could from Rarity's carefully prepared outfit, and get a desperately needed shower ... but not yet. Not now. Now was the time for warmth and closeness, to hold herself tight against the two mares she'd suddenly tied herself even closer together with. She placed the four crystals – two whole and two shards, two blue and two pink – down next to the three of them on the bedsheet ... where she could turn her head and look at them. She was almost – but not quite – sentimental enough to whisper to them ... but if she had been, she would have told them that they were four very lucky foals, to have the three best mothers anypony could ask for.

Author's Note

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