Luna's Fullest Moon

by Nostalgia Schmaltz

First published

Celestia/Luna Princest. Also a Batpony guard. Butt expansion. Sexytimes.

[/horriblepuntitle#2]

A cloppy re-imagining of the events that (would have) led to Nightmare Moon. Not much thought there, but that's not the point!

The point is Luna. Experiencing her fullest "full moon" yet. And by "full moon" I mean butts, of course. Huge princess butts.

As such, CONTAINS: Princest, Butt expansion, Batponies, and a little bit of bukakke. Enjoy!

It begins.

View Online

It was just after sunset at Everfree Castle, and as such, the moon was risen into the sky to replace the sun, albeit a bit hastier than usual. Returning from the balcony, the princess of the night sighed softly as she passed by the throne room, where her sister was getting ready to turn in for the night as well.

With her usual soft smile, Celestia stepped out just as Luna was walking past, glancing down at her. "Good evening, Luna. Are you feeling well tonight?" she asked, though Luna only grumbled softly in response, keeping her eyes straight as she continued to walk right past.

"Leave us be, Sister." Luna's horn glowed as her magic opened the door at the end of the hallway; Celestia watching with a somewhat shocked look as her sister proceeded down the hallway without even looking back at her, closing the door rather firmly behind her.

“Luna…?” Celestia blinked a couple times, still trying to grasp what had just happened while glancing idly at the closed door down the hall, hearing nothing but the fading sound of her sister's footsteps. "That's the fourth time she's acted like this...something must be wrong." she frowned a bit as she closed the door to the throne room behind her, setting off down the hall in the direction Luna had gone.

Retiring to her room, Luna sighed again, stepping up beside her bed and levitating a small locked chest out from underneath it, opening the lid to reveal a rather aged-looking book; quite old and musty, with both the cover and the back of it scratched and torn. “Soon...soon we shall be the ones ruling Equestria.” she glanced over the pages of the book as they turned with her magic, only stopping once they reached a page with a higher concentration of writing on it.

If they will not enjoy my glorious night...I shall make them enjoy it, permanently.” the night princess ran her hoof over the page as the book levitated in front of her, though it dropped back onto her bed as she suddenly heard knocking coming from her door; her head snapping to the side to look towards it.

“Luna, are you in there?” Celestia’s voice came from the other side, followed by a couple more soft knocks, along with attempts at opening the door, though the deadbolt stopped it from opening. “What’s going on, Luna?”

Grumbling in annoyance, Luna approached the door, though she stopped when she was in front of it. “Leave us be, Sister. We do not wish to converse with you at this time.” she firmly stated, before turning towards her bed once more.

Celestia only became more worried from hearing this, pressing her hoof against the door again. “Please, Luna, tell me what’s wrong. You’ve been acting very strange lately.” her magic once more tried to push the door open, though the metal bolt near the top held it back. As she leaned a bit further onto the door though, the bolt suddenly slid to the side, and with a gasp, the sun princess fell forward as the door opened, collapsing onto the floor just inside Luna’s room.

"You wish to know what is wrong with us, Sister?" Luna glanced down at her sister, almost scowling a bit now, while her magic pushed the book across her bed and under the pillow. "We are beginning to loathe our duty of raising the moon if nopony seems to desire it."

Celestia shook her head a bit as she got back up to her feet, though as she heard her sister speak, she raised an eyebrow. "Whatever do you mean, Luna? Of course ponies want you to raise the moon. Without it there would be no night time."

"And that is exactly the problem!" Luna snarled softly, glaring a bit more. "Nopony appreciates the lovely night we bring to them! They frolic and play under your radiant sun, but sleep through our beautiful night!" she raised a hoof and pointed it towards Celestia, staring directly into her eyes now. "Everypony absolutely adores you, while we reside in your shadow."

"So that's the problem? You feel like you're living in my shadow?" Celestia tilted her head just slightly to the side, remaining calm despite Luna's angry demeanor. "If that's the case, then I'd be more than willing to assist you, my dear sister." she then slowly approached, and circled around Luna, glancing over her body for a few brief moments.

"And just how do you plan on doing that, Sister?" Luna managed to calm herself a bit as Celestia approached; her head turning to watch as the other Alicorn slowly paced around her with a playful grin now.

"I think I know a way that could help you gain some...publicity." Celestia giggled softly, stepping up beside Luna now and draping a front leg over her back. "It certainly worked for me, quite a while ago." her hoof gently slid down Luna's side, circling once around the crescent moon on her flank.

Luna only gave a confused look as she was cuddled against; her cheeks blushing softly. "Whatever do you mean, Sister? How are you going to help us?"

With a playful grin, Celestia slid her hoof back up from Luna’s flank and turned towards the bed now. “Well, I’m not entirely sure if it will work or not...but it certainly did work for me.” she wiggled her hips a bit, only causing Luna’s cheeks to blush a tad deeper from the sight of that rather plump butt jiggling just enough to be noticeable.

“Sister…” Luna glared again, quickly catching on to what her sister was planning. “Participating in sexual intercourse will not solve our problem!” she stomped one of her front hooves, though Celestia only giggled again in response as she climbed up onto Luna’s bed.

“Don’t be so quick to assume, Luna my dear.” Celestia sprawled out on the soft bed, letting out a soft sigh from the wonderful plushness of the top comforter. “That isn’t exactly what I’ve got planned for you...well, not right now, that is.” when she sat back up, she gently patted her hoof on the bed, smiling warmly towards Luna. “Come, join me and I’ll begin.”

Keeping her cautious look, Luna slowly climbed up onto the bed with her sister and laid down beside her, still quite suspicious of the whole situation. “This had better not be another one of your ruses, sister.”

Celestia giggled softly as she draped a front leg over Luna’s shoulder, gently cuddling against her side again. “Trust me, Luna. I'll make our subjects adore you." as she nuzzled at Luna's neck, her hoof slid downward again, stroking over the moon on her sister's flank. "I don't want you to be depressed like this."

"Could you please inform us about what you are going to do, sister?" Luna blushed cutely once more as her flank was stroked, pouting almost cutely towards her sister now. "We wish to solve this as soon as we can."

"But if I told you, that would ruin the surprise." Celestia poked her tongue out playfully in return, continuing to circle her hoof around the moon on Luna's flank. "Just relax and let your big sister help you, Luna." she then leaned in a little closer and nuzzled at Luna's cheek, giving it a soft peck.

"If you insist, sister..." Luna groaned softly, only blushing even harder to the nuzzling, closing her eyes as well and sighing. As she felt Celestia moving beside her, she opened her eyes again and glanced to her side, watching as the sun princess stood up and repositioned herself behind Luna now, sitting back on her haunches with her eyes fixated on the purple rump in front of her. "Sister? What are you doing?"

"My, Luna! Have you been indulging in extra sweets lately?" Celestia giggled as she raised her hooves, pressing both of them onto Luna's plump rear and softly squishing it, causing Luna to groan softly again.

"Sister! Our royal posterior is not oversized!" Luna half-groaned, half-growled; quite sensitive about her proportions, though the feeling of Celestia's hooves stroking and pressing at her soft butt was rather pleasant. "If we recall correctly, it is your posterior that is larger!"

"Oh, so you're jealous of that too, are you?" Celestia smirked now, giving Luna's rear a firm squeeze which elicited a moan from her. "Don't worry, Luna my dear. I'll solve all of your problems." she then leaned down again, bringing her snout close to Luna's butt and nuzzling at the moon on her flank now, as well as slowly dragging her tongue over it. At the same time, her horn began to glow, working a specific spell on her sister's rump.

"Nnh...Sister...?" Luna gasped softly from the feeling of Celestia slurping over her flank, looking back at her and watching her worshiping those purple flanks. "Sister! We told you that we do not wish to engage in that type of activity!"

“Mm, come now, Luna...such a lovely posterior deserves attention.” Celestia kept her playful smirk as she continued to nuzzle and slurp at Luna’s cutie mark, while her hoof gently slapped the Alicorn’s other flank, eliciting a soft gasp from her. As her horn kept glowing, more of her magic channeled into Luna’s rump, which was now beginning to swell larger and softer, albeit at a slow and steady pace. “By the time I’m finished, nopony will be able to ignore it, hehe…”

Due to Celestia’s magic, the teasing spank caused pleasurable tingles to ripple through Luna’s rear as it lightly jiggled; a soft moan escaping the night princess’ lips as her eyes midclosed. “Sister...what spell is this?” she gasped softly again as she felt her sister’s hoof strike her plump cheeks once more, sending another wave of tingling through them as they jiggled.

“You should know this one, Luna...at least, I’d expect you would.” Celestia giggled softly as she lifted her head, placing both hooves on Luna’s swelling flanks again and gently massaging over her cutie marks, watching as her sister’s rear slowly expanded with the magic filling it. “Yes, that’s it...grow nice and plump, sister.”

“Plump? What are you doing to our royal posterior?” Luna looked back again, now noticing that her butt had swollen noticeably larger against Celestia’s hooves; her eyes widening in both surprise and slight arousal to this revelation. “Sister! You are making us...bigger?”

With another soft giggle, Celestia nodded, still massaging Luna’s ever-swelling rear with both of her hooves, stopping only to squeeze the two soft cheeks towards each other for a couple moments. “Of course, dear sister...nopony will be able to ignore such a huge butt.” she grinned and raised both of her hooves a bit, gently spanking both of Luna’s cutie marks at the same time.

“Ah!” Luna gasped cutely again from the spank, feeling much more pleasure than before; the plump buttcheeks having become quite sensitive from their magical swelling. “Sister...nnh...we cannot be seen like this! We look ridiculous!” she protested, despite the strange new feelings of pleasure that her huge rump was providing. “Change us back at once!”

“Oh, Luna...I know our subjects well. None can resist a royal posterior.” Celestia grinned playfully again, giving Luna a slightly harder spank which elicited another moan from her. “Here, I shall prove it to you.” she turned her head towards the door and pulled it open with her magic, before her aura grasped a pull-string beside the door, which signaled the guards to that room. Glancing back down at Luna again, she slid her hooves up the Alicorn’s back, gently stroking under her wings. “Now, just wait for the guard to arrive, and you'll see just how much your royal rump will be adored.”

“We are still unsure of this, sister.” Luna gulped softly, turning her gaze towards Celestia as she felt the larger Alicorn cuddle up beside her again, while her ear twitched softly, picking up the sound of galloping hooves coming down the hallway. Just moments later, one of Luna’s bat-winged guards trotted up to the doorway, glancing into the room.

“You called, Princess Lu…” his voice trailed off almost immediately after his gaze met the dark-purple royal posterior that was facing the doorway, completely overshadowing the white one next to it. Immediately, his cheeks flushed with embarrassment; unable to avert his eyes from that luscious butt no matter how hard he tried. After only a few seconds of staring, he could already feel a certain swelling between his legs, only causing his whole face to blush now.

“Yes, we did, our guard." Luna turned her head to glance back towards the door, her own cheeks cutely blushing as she noted the guard's exasperated look. "We wish to know your opinion of our posterior, guard." she stated rather calmly in the same way she would give an order; the guard gulping nervously in response.

"It's...uhhh..." he stammered, averting his eyes repeatedly, but his gaze only managed to leave the princess' rear for brief moments at a time before returning to it. "It's very...large, Princess." he finally managed to respond, trying his best to avoid offending the princess, or sounding too lustful. "I think it...suits you well?"

Despite his simple wording, Luna could easily tell his actual feelings; now spotting his growing erection down lower between his legs, watching it throb and twitch to its full size, with the tip flaring out powerfully from the sheer amount of arousal the stallion was feeling. "Hm...is that so, guard..." she turned back towards Celestia again, glancing expectantly towards her; not exactly sure how to proceed.

Celestia grinned in response, giving Luna's snout a soft nuzzle before turning her gaze towards the still heavily-blushing guard. "You seem quite interested in my sister's rear, guard. Perhaps you would like to give it a closer examination?" she winked towards the stallion while her horn glowed again; her magic brushing against his flanks and gently nudging him forward. "She's unsure of whether or not her subjects will approve of it. Why don't you console your princess a bit?"

The guard barely caught Celestia's words with so much of his attention focused on the massive butt in front of him; shaking his head for a moment before looking up at Celestia. "A-as you wish, my princess." he gulped softly again and slowly approached the side of the bed, raising his front legs up onto it while keeping his gaze locked on Luna's huge rump; his erection throbbing wildly with arousal while thoughts of plowing the night princess flooded his head.

"Go on, our loyal guard. You may do as you please." Luna lightly wiggled her waist, causing her fat butt to jiggle with it, only teasing the guard further. "Show your princess how much you adore her royal posterior."

"Oh, sweet Celestia...if I'm dreaming, don't wake me up!" the guard grinned now, watching as that massive Alicorn butt wiggled and jiggled before his eyes; its plump cheeks jiggling almost like gelatin from how wondrously soft they were. Bringing both of his hooves up further, he placed them on both of Luna's cutie marks and began to pull himself closer; the pressure from his hooves allowing him to feel just how soft the princess' buttcheeks were.

"Princess Luna...it's...magnificent!" his grin widened while his hooves continued to lightly press and squeeze at Luna's rump, now able to feel its soft jiggling and wobbling with every movement. "I've never seen such a magnificently large rear, my princess!" he continued to scoot forward little by little, pulling his waist closer to Luna's posterior until his rock-hard erection finally began to press against it, causing Luna to blush once more.

"We are glad to hear it, guard." Luna smiled to the compliment, though she gasped softly as she felt the guard's shaft pressing against her inflated rear, feeling it throbbing rapidly in time with his heartbeat. "Mnh...we implore you, guard...show your princess just how much you adore her." she then pressed back against the stallion, causing his member to become squished between her plump buttcheeks, almost completely surrounded by the immense softness.

"A-aahh...Princess...!" the guard's hips instinctively started to buck almost immediately after Luna's soft buttcheeks encased his shaft; his hooves squeezing more firmly at her cutie marks as he hotdogged his shaft between the two plump cheeks, already smearing a couple loose drops of precum between them. "So soft...nnh, it is truly wonderful!" he groaned, closing his eyes and panting softly as he kept thrusting his member against Luna’s rump.

“See? I told you it would work, sister.” Celestia giggled softly as she watched the guard eagerly hump Luna’s rear, before glancing towards the Alicorn’s face, seeing her still blushing, with her eyes midclosed. “With such a delightfully large butt, you’ll be ignored no longer.” she leaned in closer and gently nuzzled at Luna’s cheek, giving it a soft peck.

“Mmnh...we thank you, sister...we are most grateful for your gift.” Luna spoke between her soft moans and light panting, nuzzling back against Celestia’s snout. “We shall...ah, see how some of our other subjects respond to our new endowment, later on.”

With a soft smile, Celestia nodded, before standing up on top of the bed; looking back at the guard again, who groaned out loudly as he suddenly climaxed, spurting his load all over Luna’s rear and lower back, which only caused her to blush even harder. She smirked playfully to this sight; still quite aroused herself from all of the teasing she did to Luna, with most of those naughty thoughts still lingering in her head.

“Dearest sister...don’t you think some repayment is in order?” Celestia spoke again as she moved in front of Luna now, sitting down on her haunches again with her moist nether lips in clear view to Luna. “After all, I helped you...it would only be right for you to help your big sister in return.” she grinned down at Luna, while her clitoris winked a couple times before the night princess’ eyes.

Luna bit her lip softly from the sight of her sister’s sex, especially as it winked teasingly to her. “Sister…” she looked up into Celestia’s eyes for a moment, finding comfort in that soft grin for a moment before glancing back down again, seeing that big clitoris wink once more. With a lustful groan, she slowly leaned her head down between Celestia’s thighs and began to nuzzle at her warm sex, giving it a single slurp as well.

“Mmnh, that’s it, Luna dear…” Celestia sighed contently to the teasing her pussy was receiving; placing one hoof on Luna’s head and gently stroking it through her mane while she glanced down at the guard again, who was still panting in the afterglow of his orgasm. “Do not cease, guard...continue to please your princess’ large rear.” she grinned playfully towards him, though he looked a bit distraught. “That’s an order.”

Although his orgasm had taken out a good chunk of his stamina, his hooves squeezed at Luna’s butt again as he positioned the tip of his shaft at her rear entrance, which had become smeared with his semen from his previous orgasm. “Nngh, yes, Princess Celestia.” he groaned, before pushing his hips forward and penetrating the night princess. Immediately, his eyes widened again from another surge of pleasure; Luna’s backdoor having become exceptionally tight as a result of her growth, a tightness that rivaled even that of a virgin! “Ah...! Oh, dear Princess, it’s so tight!” he groaned out loudly while his back-leg muscles spasmed a bit, eager to push himself even deeper inside that snug entrance.

Just as the guard penetrated her rear, Luna groaned out loudly into Celestia’s snatch, pushing a little more firmly against it while her tongue pushed firmly inside; her eyes opening wide just as the guard’s did, from the mix of pain and pleasure coursing through her lower regions. “Mmpmh….mmm!” she moaned into her sister's sex, now finding herself slurping her tongue along the soft inner walls, which were quite moist with sweet royal nectar.

"Ooh, it should be, my guard..." Celestia let out a deep sigh as she felt Luna's tongue push inside her and begin to tease her sensitive insides, still stroking along the soft purple mane while she watched the guard push his hips firmly up against Luna's rump. With each thrust, he pushed a few more inches of his length inside, smearing warm precum the whole way. "It should be the tightest in all of Equestria."

"It certainly feels that way, nngh, Princess!" the guard grunted with his last push, sheathing nearly all of his length inside Luna's rear before pausing to enjoy the wonderful tightness; his cock being squeezed so firmly by the lunar princess' insides. Luna could feel each and every throb that stallionhood gave inside her, only serving to arouse her even further and make her quite anxious for the bucking to come.

Leaning forward now, the guard slid his hooves up Luna's back and pressed them just below her wings, before his hips began to pull back, slowly sliding his member out of the snug backdoor that was squeezing it. With only a few inches still inside, he thrust his hips forward again, groaning in unison with Luna from the wonderful feeling before repeating the motion again, and then again, quickly working his way up to a steady bucking, feeling his hefty balls slapping against the princess' oversized butt each time he thrust inside.

The guard's bucking only pushed Luna to increase her efforts as well; closing her eyes tightly while her tongue delved deeper into her sister's heated sex, eagerly dragging along the silky walls and tasting the sweet juices within. "Mmnh...mmnh...mmm...!" she groaned out each time the guard's hips smacked her huge buttcheeks, only adding to her own pleasure.

"Ooh, yeah...keep that up, Luna!" Celestia leaned back and let out a pleased moan from the feeling of Luna's tongue pushing further inside her; her hoof still stroking over Luna's mane and gently pushing on her head, as if trying to push that snout even more firmly against her nether lips. As she enjoyed her sister's oral work, her horn began to glow once more. This time, her magic focused on the guard and pushed at his waist, putting a bit more power behind his thrusts.

"Ahh, P-Princess..." The guard panted and grunted as he felt himself pounding Luna's snug rear even harder, smacking his crotch firmly against those soft purple buttcheeks with every thrust; their softness only adding to his pleasure each time his cock brushed along them on the way out. "I'm...ngh...I'm going to...ah, c-cum soon!" he groaned between his thrusts, feeling a second orgasm building up very quickly despite his previous orgasm being just minutes ago. The tight squeeze of Luna's insides along with his huge arousal from the situation were easily overwhelming him with lust; his hooves squeezing tighter at Luna's sides to brace himself during his rough pounding.

"Already, huh? Perhaps I should, ah...train you guards better..." Celestia teased with a playful smirk towards the guard, still pushing and pulling his hips with her magic. "Surely no royal guard would, nnh, cum before his princess...right?"

"Of course, Princess!" The guard bit his lip as he tried to slow his thrusts, but Celestia's magic kept up his pace, forcing him to pound Luna's ever-squeezing rear. "Ngh...f-fuck...gotta...hold off!" he closed his eyes and tried his hardest to imagine unarousing things, trying desperately to ignore the massive royal rump that his stallionhood was relentlessly pounding, but to no avail. The tight squeezing was milking gush after gush of pre from him, splattering all along those soft insides while his orgasm drew closer with each passing moment.

Luna was too absorbed in her cunnilingus to pay any attention to the banter between her sister and the guard, though the pleasure from the rough pounding was starting to catch her attention as it built up more and more within her loins; her own carnal juices dripping onto the bed below as a result of her own impending orgasm. With one hoof around Celestia's waist, her other hoof slid down between her legs and began to rub over her own sex, eliciting muffled moans into Celestia's pussy as she kept up her oral work.

"Ahh...I can't hold it back much longer!" The guard's hooves were now pressing against Luna's body, desperately trying to slow his thrusts in any way he could as he felt his balls start to pull up closer to his body and contract; about to release their load any moment now. Just moments before he thought he was going to cum, Luna's insides began to squeeze his meat tighter than ever before, causing his eyes to widen as he moaned out blissfully.

With one final thrust, the guard buried his length inside that royal rump and leaned his head back, his wings flapping wildly from the rush of euphoria while his member spasmed wildly, releasing gush after gush of seed. "Ooggh..Princess Luna!" he panted, closing his eyes tightly as he painted the princess' insides completely white.

At the same time, Luna groaned blissfully into her sister's snatch while a torrent of her royal juices flowed from her own sex, splashing onto the bedsheets below. The rush of warmth filling her backdoor only seemed to amplify the pleasurable tingling that her orgasm provided; her eyes rolling back in her head from all of the euphoric feelings, though her tongue kept going, firmly slurping along Celestia's silky inner walls.

"That's it...mnh...my lovely guard, fill your night princess..." Celestia gently licked her lips as her magic continued to stroke the guard's sack, feeling the two orbs contracting powerfully to release a few more spurts of seed before the stallion's orgasm finally subsided. Eager to have a nice orgasm for herself, Celestia brought one of her hooves down between her legs and pressed it against her clit, panting deeply from the built-up pleasure within her that was quickly reaching its peak, only pushed even harder by the firm rubbing her love nub was receiving. "Ooh...Luna...!"

Throwing her head back, the sun princess cried out blissfully as she finally reached her own climax; her hips bucking forward just a little against Luna while her own torrent of juices gushed forth, splashing all over Luna's snout and into her mouth as well, flooding it with the sweet flavor that her tongue had been slurping up.

With the exhaustion from two powerful orgasms in such a short time frame, the guard let out a soft groan before he collapsed on Luna's back, panting heavily while his spent member continued to lightly throb against the tight squeeze of the princess' insides. "Nhh...my princess...are you...pleased?" he weakly moved his head to look forward, seeing the night princess' head still buried between Celestia's thighs.

Luna was doing her own fair share of panting from the rush of sensations; her mouth filled with the sweet nectar of her sister, while her rear was stuffed full of warm, thick liquids which slowly oozed out around the guard's endowment. With one more slurp at Celestia's sex, she sighed contently and lifted her head, turning to glance back at the guard. "Very much...mm, my loyal guard." she smiled softly now while her cheeks cutely blushed again. "Your services are are no longer needed for now. Begone until we summon you once more."

"Oh, yes, as you wish, Princess." The guard smiled in return; satisfied enough with the princess' orders that he didn't particularly care that he was already being dismissed. Gripping at Luna's sides again, he pulled his hips back and slid his softening member out with a soft groan, enjoying the tight squeezing one last time as the flared tip slipped free of the royal rump. As he left, Celestia grinned down at her sister, still gently stroking a hoof over her head.

"Do you see now, Luna? I told you that nopony would be able to ignore such a delightfully large butt." Celestia giggled softly as she repositioned her body again, laying beside her sister once more. "You must be even bigger than me, sister. I don't think you'll ever have any problems with being ignored." she poked her tongue out, getting a soft giggle from Luna in response.

"We suppose so, sister...it does feel rather nice having a large posterior." Luna smiled in return, still blushing lightly as she glanced back at her swollen rump, a few streaks of the guard's seed still splattered across it and her lower back.

With a playful grin, Celestia leaned against Luna and nuzzled at her neck, cuddling up against her side. "Glad to hear it, little sister. I'm always happy to help with anything that troubles you." she then leaned her head up a bit and affectionately slurped at Luna's lightly-blushing cheek, giving it a soft nuzzle as well.

“We are most grateful, sister. But judging by that guard’s reaction, we will probably need to train them not to stare.” Luna giggled softly, gently leaning her head back against Celestia’s to return the gentle nuzzling.

TEH EDN, I suppose.