Celestia and Luna Have a Difference of Opinion About the Merits of Tentacles

by Crimson Prose

Rating: mature
Tags: Slice of Life, My Little Pony: Friendship is Magic, Princess Luna, Porn, Fetish, Comedy, Princess Celestia, Sex
Length: 3119

Celestia plays a prank on Luna. Luna has mixed feelings about the situation and voices her concerns to her sister. Very friendly tentacles, all-the-way-through, and oviposition ensue.

Celestia plays a prank on Luna. Luna has mixed feelings about the situation and voices her concerns to her sister. Very friendly tentacles, all-the-way-through, and oviposition ensue. (Thanks for the feature on 8/15-17/2023!)

Tags: all-the-way-through, anal, blowjob, cum drinking, double penetration, dubious consent, exhaustion, horn job, impregnation, oviposition, reverse blowjob, tentacles, triple penetration, vaginal

Based on an image by Jcosneverexisted, which can be found searching relevant keywords on pony boorus. My subscribestar, fan club, Discord server, or commission info..

Published 2023-08-14 11:10:00 UTC
Last updated 2023-08-14 11:10:00 UTC

It's Just a Prank Sis

“Why exactly are we here again?” Luna asked Celestia as they trotted down a path in the middle of the Everfree Forest.

“Is it so wrong that I want to spend some time with my dear sister?” Celestia asked, eyes shifting back and forth slightly.

“When it’s something like this, yes,” Luna deadpanned in return. “Because it usually means you’re about to play a prank on me and I’m not in a pranking mood.”

“Oh you’re just being paranoid,” Celestia assured her. “Trust me, I found something during my last walk here and it is… well something I think you’ll remember fondly.”

“Are you going to tell me what the ‘thing’ is?” Luna arched one eyebrow, looking suspiciously around the dark forest. “And are you sure we shouldn’t be flying?”

“Just come and see!” Celestia said. “And yes I’m sure. Like I said, I want to spend time with you. Now why don’t we talk about something more fun.”

“Like what?” Luna hmed.

Celestia glanced around the forest too, trying to be less obvious about it. They should be getting close enough now for it to notice them, and once it did…

“Um well,” Celestia tried to come up with something distracted. “Can you guess what I walked in on Twilight doing the other day?”

“Was it her brother?” Luna deadpanned again.

“Oh I guess I told you that story,” Celestia said. “Well can you guess what I walked in on Cadance doing?”

“No and I don’t want to know,” Luna said. “Seriously don’t ever tell me what that slut was doing, I avoid her dreams for a reason. Her activities give power to my nightmares.”

“Oh you need to loosen up a bit, dear sister,” Celestia said. “Maybe this will help.”

“What’s that supposed to-” Luna started, but her words were cut off by a shriek as something lashed out from a nearby bush and wrapped itself around one of her hind legs.

“There it is!” Celestia said. “I mean… oh no what could that be?”

Luna immediately charged up her horn for an attack, but the tentacle seemed to already be nullifying her magic as it clamped more firmly around her hoof. She shrieked as a second vine snagged her other hind leg and for some reason seemed intent on pulling her hind legs apart. She knew exactly where it was going when tentacles did that, so took off to try to flee, beating her wings as hard as she could, but didn’t get more than a few hoofsteps off the ground before she was pulled back.

“Oh no,” said Celestia unconvincingly. “I’ll save you dear sister.”

With that, Celestia calmly trotted over, then dramatically tripped over a rock, which put herself directly in the path of another tentacle that was streaking towards Luna. The tentacle was pinned to the ground by Celestia’s heavy body, then wrapped around her waist to begin sapping her magical energy as well.

“Oh no I’ve been captured!” Celestia said as she rolled over onto her back and splayed out all her limbs, wings outstretched against the ground and legs up in the air. More tentacles snapped out of the darkness and began to lack around her, dragging her against the ground and towards the bushes.

“I swear you’re no better than Cadance sometimes!” Luna growled, trying much harder to keep herself from being dragged in. Before she could try to beat the tentacles away with her front hooves, they were captured as well, her wings grabbed so she could no longer fly, and several more latching themselves around her torso. It took twice as many tentacles total to drag Luna at the same rate as Celestia, the dark princess thrashing and screaming in frustration and rage.

“I’m just helping you relax!” Celestia claimed. “You’re always so pent up!” Her body was easily dragged across the ground, her rump pulled into the nearby bushes as her hind legs were spread further apart. She licked her lips, waggling her hips a bit in anticipation of what was to come, a wide grin on her face that she didn’t bother to hide at this point.

“Has it occurred to you…” Luna groaned as she thumped to the ground, writhing and leaving far messier drag marks as she was pulled towards the pushes. “... that it’s sapping our magic? Do you really think it’s just going to let us go when it’s done with us? Does anypony even know we’re here?” She clamped her tail down as she was dragged in, but another tentacle pulled that up as well, pulling it far enough that her bottom lifted from the ground slightly.

“Anycreature, remember we’re being more inclusive lately,” Celestia corrected her. “And of course! I instructed Twilight to bring us potions of anti-magic resistance if we didn’t return, so there’s nothing to worry about. Just relax and enjoy the moment! We’re alicorns so our bodies are plenty resilient enough to take any punishment this thing cares to put us though.” She knew because she’d tested it thoroughly.

“Why do you always do this?” shrieked Luna. “Over half the time your pranks involve me getting fucked in some way. I’d still be a pure virgin if not for you!”

“You’re welcome,” countered Celestia simply. “And even though you’re complaining, I know you always get into it. I’m starting to think being tsundere is one of your fetishes.”

Luna’s struggling was only making the vines more interested in her, and she was the first to feel the slimy prodding of phallic plant life sliding over her vulva. She squeaked, moving her hips around to try to avoid it, and the plant seemed to enjoy the chase rather than holding her still initially.

Celestia on the other hoof didn’t even really need to be held at all. She perked her rump up in the air and waggled it slowly back and forth, mmm-ing when she felt the sticky feel of tentacles lashing up and down between her labia to get her wet. She shivered as it pushed its way inside, stretching her lips over its smooth surface, pumping in several times all the way to her cervix before pulling out with a lewd pop. It then moved up to her tailhole, intending to use her pussy juice as lubricant there as a second tentacle pushed against her pussy.

“That’s it, buck yes take us…” Celestia groaned.

“Don’t say ‘us’ like you speak for me,” Luna said, but all the same realized there wasn’t any way out of it. Huffing slightly, she stopped wagging her rump and braced herself against the ground, clenching her teeth and her holes. She tried to loosen up the latter of the two, but they weren’t cooperating.

Luna’s resistance seemed to make it think it had to be faster with her, so her slit was speared roughly from the start, pumping into her cervix deep before sliding out and moving to her rectum as well. There it stiffened and speared her again, causing her whole body to tense as another one slid no less gently into her pussy.

That was the end of any gentleness as the tentacles went deep and fast. Suddenly the quiet path was alight with the sloppy sounds of slimy tentacles in equally slimy holes.

Each thrust into their pussies flicked their soft lips back and forth, juice drooling down their thighs as their breasts beneath them bounced to the rhythm of the thrusting. The bottoms and the tentacles were shiny with the glistening pussy juice as it speared right up through their cervix, pushing into their royal wombs, seeming to split at the end so each part could wind all the way up, filling them all the way to their ovaries.

The thick rods in their ass showed every bit the same enthusiasm, their pucker sliding over the slick surface. They had a lot deeper to go however, and kept working another inch inside with each thrust. It wasn’t long before it was outright winding its way through their intestinal tract, stretching them out deeper than should even be possible.

“You can’t tell me you don’t love this!” Celestia groaned, arching her back as her hips rolled in response. She’d been anticipating this for hours today, and her hind legs were already shaking violently as she peaked and creamed over the hot wet tentacles pushing through her. She splattered her juice so far that Luna felt the spray against one of her thighs.

“You’re insane!” Luna shrieked in return, but followed it up with a squeal. She wasn’t over the edge yet, but it was hard to deny she was going that direction with the way things were going. She tensed her whole body up, straining to hold it back lest her sister believe she enjoyed it more than she did. “S-sister, I hope they rescue us soon. I can’t resist those tentacles anymore.”

“Calm down my sister,” Celestia said, her eyes rolling slowly back in her head as her limp body shook with each stroke. “This is going to get ‘better’.”

“What do you mean-” Luna started, but then her shriek went up a few octaves.

The timing was so good that Luna started to wonder if the tentacle monster was actively in on it with Celestia. The previously smooth flesh of the whips of textures flesh undulated, then sprang forth spiny protrusions all over the surface. Fortunately an alicorn’s body would be tough enough to stretch around the spikes, but that didn’t mean she wouldn’t feel it.

Soon the myriad barbs were dragging back and forth inside them. Each thorny protrusion raked across their sensitive labia, flicking their lips back and forth with each stroke, grinding their vaginal passages womb-deep in the process. Their tail holes got the same treatment, perhaps more so because they had continually gotten deeper this whole time, winding up through their tract and somehow stimulating depths that they shouldn’t have been able to feel.

“Hnnnghhhhh,” Luna clenched her teeth as her eyes widened. “W-what even is this thing? Why would a creature have magic to make someone feel their insides like this?” Her whole body twitched violently, legs kicking wildly. She strained so hard to hold in her orgasm that she felt her teeth creaking, but in the end couldn’t hold it back. She exploded a jet of thick pussy juice over the raking thorns, drenching her own hindquarters with viscous goo beyond what the disgusting creature had coated her with.

“Aaaaaahhhhh!!!” Celestia cried out, laying her head on the ground with her tongue out, drooling a puddle as her eyes rolled into the back of her head. “I-I think it might have been someone’s toy experiment that escaped.” Celestia had never stopped cumming herself to begin with, and was spilling out so much pussy juice that it’d be a wonder if she didn’t need treatment for dehydration when it was all done. Unlike Luna though, her body was completely relaxed, rolling her hips back freely and letting her body bounce back and forth with each movement of their affectionate defiler.

“It was yours wasn’t it!” Luna screeched the accusation, then broke into a fit of coughs as she felt her neck swell much like her bloated body had. Her eyes went even wider as she felt the other end of the ass tentacle exiting her throat, spilling out of her muzzle and whipping about like a frantic tongue. It still shifted back and forth a full foot as her entire system was fucked, ramming her ass on one end and getting a reverse blowjob on her head end. The very end whipped upwards and grasped her horn, sliding its slimy surface up and down in stroking motions as well.

“I had almost nothing to do with it!” Celestia claimed. “It’s Cadance’s creation I only helped a little bit in the testing phase!... oh fuck that’s it all the way through just like last time!” Celestia showed a disturbing lack of gag reflex as the monstrous tentacle exited her muzzle, twirling her tongue around its length to feel the spiny barbs that were so wrecking her system. Her’s whipped further upward, grasping at her horn and playfully as well. She tilted her head forward to let it reach, then groaned more at the stimulation to her horn.

“How long-” Luna managed to blurt out a few words each time the throat tentacle pulled back. “Before… help…” At the very least though Luna had begun to relax, and whether from will or instinct her hips were pressing back against her defiler now as they continued to stroke into her sweaty writhing body. More tentacles slid around her torso and neck, giving her a thorny massage.

“Not long-” Celestia responded. “No more than… 12 hours…” Celestia couldn’t help but smirk a bit after giving that answer, at least until the smirk was broken by the next vomiting thrust of the tentacle out of her throat. She had her whole body pressing back with far more obvious intent as she was surrounded by more fleshy prickly vines, waggling her ass back as her pussy continued to convulse around the invading tentacles.

Luna’s eyes widened at the answer, but didn’t have much of a response. Any response she gave would probably just make her big sister hornier anyway. Besides that, she had to admit she was getting into the moment, and knew from experience with Celestia’s previous pranks that she could certainly handle longer than that and still have little more than a pleasant ache to show for it. Alicorn regeneration was both a blessing and a curse.

Though her relaxation ended when she felt the tentacle digging into her womb bloat noticeably, a thick round swell push through starting at the base and stretching out her passage as it proceeded towards her womb. Another followed, then another after that. Luna tensed and kicked her legs frantically again, but by this time she was completely tangled in vines and couldn’t have kicked free no matter what.

“Sister! I think it’s… laying eggs inside me!” Luna screeched before gagging up a tentacle again. The slimy tentacle popped out the first egg, snuggling it into one corner of her ovaries with such a loud slurp that one could hear it from within her even above all the other grotesque noises. More were still coming out of the base, a good half dozen headed into her womb already.

“Well of course,” Celestia groaned out. “You didn’t think… it just grabbed ponies… and fucked them… solely for fun did you?... Don’t worry… Cadance says… they actually… feel quite nice… when they squirm back out of you… it won’t… burst out of your chest… or anything like that.”

Celestia took it far more happily, groaning and arching her back, intentionally squeezing and loosening her tunnel to massage the eggs as they were pushed up inside of her. She wrapped her tail approvingly around the hollow tentacle that was loading her up with its young, and began to bob her head as she licked her tongue around the vine in her throat.

“I did not… sign up for… this!” Luna shrieked. This shriek was less from pain or fear and more because she ended up creaming herself again, her body betraying her as her viscous gunk splattered out from around the vine loading up her pussy.

“Of course,” Celestia somehow kept her smirk even while intermittently vomiting a tentacle. “That’s what… makes it a prank!” Her pussy was spasming too, but more in a constant state of orgasmic bliss, unable to stop creaming herself. Luna peered over at Celestia’s drenched behind and hoped that her sister drank plenty of fluids before putting this insane plan into motion.

Luna felt her belly start to swell visibly as she was loaded further. It finally pushed the last one up through her, but by then her womb was stretching like an overfilled water balloon, the gel-like eggs making her whole gut wobble almost comically with each rabid thrusts into her. The plant didn’t seem done just because it’d placed its young inside them, not breaking the intensity of the pumping even now.

For a moment, Luna wondered if the creature might eventually stop once it was finished, but it seemed content to keep going. Even as all of their holes leaked the slimy secretions from the tentacles, it continued to ram through their whole bodies, defiling them to impossibly deep lengths.

Fortunately it seemed like the vine worried about dehydration too, because another tentacle stuffed Luna’s muzzle. The one coming up from beneath didn’t stop thrusting through her, but this one began to pump a sweet-tasting slime into her throat. She had no choice but to swallow it down, even knowing that it was probably the equivalent of the plant’s cum. Or pollen? She didn’t care, she was thirsty as fuck.

“Yeah, give me that juice…” Celestia groaned as soon as she saw the tentacle, apparently expecting that part as well. She drank from it a lot more erotically, bobbing her head and playing her tongue around its circumference as she slurped down the gooey goodness that it offered.

Luna started to wonder if this thing was more intelligent than it was making out, and if Celestia had carefully planned how this would go beforehand with the tentacled beast. It’s not like Celestia would put their lives at risk for the sake of a prank after all. Probably.

This treatment continued as Luna lost track of time. For hours her entire world became the undulating tentacles in and around her, draining her through orgasms and sweat before filling her up with more fluids for another few hours. It seemed in no danger of stopping, and whatever it was feeding them gave them enough energy to keep up their struggle seemingly indefinitely.

“Celestia! Luna!” another voice ran out finally above them. It was Twilight. Had it already been 12 hours? Time sure flies when you’re having something akin to fun.

“Oh… thank… me…” Luna groaned…

Only for her relief to instantly be shattered. As Twilight swooped close, a tentacle whipped out, grasping one of her wings and sending her headlong into the bushes between them. The potions that she’d been supposed to feed them to let them get away smashed on the ground, their contents soaking uselessly into the dirt.

“Hey, that wasn’t part of the deal!” Celestia said as Twilight was wrapped up in tentacles too. “Not that I mind this turn of events… don’t worry Luna dear, it’ll wear out within a day or two.”

“You have… GOT… to be… KIDDING … me!” Luna shrieked.

Celestia wasn’t kidding.