Rainbow Dash sat on one of the uncomfortable seats in the waiting room of Ponyville hospital. She was focusing intently on watching a particular light blink on and off above a door. It was an old exit sign, and like all of its ilk it flickered. Rainbow Dash was starting to see deeper meaning in the pattern of the flashes. She counted them: 1 flash, 1 flash, 2 flashes, 3 flashes…

Of course, Rainbow Dash was doing this for a very good reason. She didn't want to think about the things squirming inside her. When she thought about the things squirming inside her, it resulted in her squirming too. "Will the doctor be much longer?"

Nurse Redheart was coming up on the end of a long triple-shift. She was wanting nothing more than to clear the waiting room so she could slump somewhere and sleep for a month, but instead she had a damp Rainbow Dash with a squirming belly sitting there, dripping on the seat and the floor. "Again? We told you last time, this isn't—"

"Can't you just give me something that will make them clear out?" All pretense was lost now. Rainbow Dash had to address the elephant in the room—or the tentacles in the butt, as the case may be—or give up and leave. "What's the strongest laxative you have? Give me a double dose and a prescription for prune juice!"

Delivering what even Princess Twilight Sparkle would call a professionally done face-hoof, Redheart let out the smallest whinny of defiance against a universe that seemed intent on ruining her hopes and dreams. "Firstly, you don't want the strongest laxative we have—the last pony who got it went from Ponyville to Canterlot in twenty seconds. Secondly, you can't get a prescription for prune juice."

Knowing more than everypony else, Rainbow Dash puffed out her chest-fluff in defiance. "But Granny Smith has one!"

"Doctor Horse gave her a prescription for prune juice so that she could tell Applejack she had to drink it. Granny Smith likes prune juice, but knew her granddaughter would go into seizures at the thought of her not drinking apple juice." Redheart disliked only one thing more than a pony being needlessly in pain, and it was a pony needlessly being a pain. "Now, thirdly, we can't get that thing out of you—" Redheart paused as Rainbow, like a missile, left the emergency room, "—with prune juice because they live on sugar byproducts. That would be feeding it."

Not hearing the last words of sage advice that Redheart was trying to tell her, Rainbow Dash was making for the Ponyville drugstore as fast as she could while also clamping her tail down. Pushing the door open, Rainbow froze in place as the thing pushed its way into a new part of her body.

This wasn't the first time Rainbow had been beset by overly invasive tentacles. They were considered a minor pest, found only in some warm springs around the Everfree Forest—which just happened to be the best places for a pegasus to relax after a heavy workout routine.

Walking up to the counter, Rainbow Dash was surprised to see Derpy Hooves working. "Uh, hi Derpy. I thought you worked at the post office?" Another squirm inside her caused the last word Rainbow spoke to go into an octave no stallion could ever hope to explore.

Laughing a little at the silliness of her next customer, Derpy snapped off a sharp salute. "Uncle Pill Popper really needed somepony to work here today, and I had some holidays I hadn't used. What can I get you?"

Suddenly glad she didn't have a prescription for anything, Rainbow breathed out a sigh of relief. "I need some laxatives and prune juice."

Derpy's wings shot up in surprise, then she tilted her head to one side, and when she still couldn't work out what was going on, she stuck her tongue out the corner of her mouth. Everything came together when she remembered last time. "Oh! You've got tentacles in your butt again? Didn't Fluttershy hel—"

"Fluttershy's off on a friendship mission with Pinkie Pie. I need these things out, and short of Fluttershy asking them nicely or wrapping my lips around a party cannon, I figure I'll blast them out chemically!" By the end of her expert diagnosis and solution, Rainbow had her wings out and her chest puffed up. The image may have been ruined by her tail shooting nearly straight up when something pushed its way out of her butt, however. "Make it fast!"

Turning around, Derpy's eyes tracked among all the medications until she spotted just the right thing. "This one!" Grabbing the bottle with a wing, she turned to see Rainbow studiously ignoring the green tentacle that was now coiled around her back left leg. "Are you okay?"

"Just—Just fine. C-Can you give me the pills and the—the—" When Rainbow felt a second tentacle creep out of her tailhole and slither slowly down her taint to her vulva, she stopped talking, whimpered just once, and bolted out the door of the drugstore as fast as she could.

Derpy's wings tucked back down and she set the bottle of pills on the counter. "I guess she likes having them?"

Spreading her wings, Rainbow Dash shot into the sky. Her coat was practically dry now, but the tentacle exploring her netherparts was becoming more insistent about gaining entry to her pleasure cavern. At least, those were the words Rainbow Dash was trying to not think about as a green tendril snaked its way into her vulva.

Landing on her home's cloud, Rainbow was inside the door and rushing to her bathroom in less than a second. Never before had she been so thankful for the huge mirrors that Rarity had insisted she needed to look her best. Turning, Rainbow looked in one mirror, which looked at another mirror, and a third one, which showed a third tentacle squirming out of her butt.

Whining, Rainbow Dash closed her eyes so she couldn't see the tentacles. For nearly ten minutes she stood there, trying to ignore the sensations that felt wrong and good in equal measure. "No!" Her resolve reasserted itself and Rainbow opened her eyes. Both her back legs had a tentacle gently wrapped around them, and the one leading from her ass to her pussy was shifting slightly—but she already knew all this from how incredibly turned on she was. "Just stop!"

When the movement inside her ceased, Rainbow stared at the unmoving green things in the mirror. "Are you guys seriously going to do what I tell you?"

The moment of peace lasted an hour. Rainbow had adjusted to the new normal by settling on her couch with a Daring Do book to avoid thinking about what was happening.

At last, as if they too were bored, the tentacles all pulled back. Rainbow arched her spine and let out a wordless squeak of shock as the one in her vagina withdrew, and she felt each of her back legs freed. The downside was her belly was extra-full now.

"This is—This is somehow better. You okay to stay in there while I find somepony to help?" For a second Rainbow felt silly for talking to the tentacles currently residing in her colon, but it seemed to help the first time. "Right. I'm heading out to talk to Twilight. She'll work out what we can both do to get you where you belong and me—me rid of you."

A gut-twisting clench made Rainbow bit her lip and gasp. "Hey! You can't stay in there forever. How am I meant to go to the bathroom like this? Or fit into my flight suit for that matter. Look, if you need a little more time to do—I don't want to know what—stuff, that's okay, but you have to come out sometime."

When she felt no disturbances from her intruder for several minutes, Rainbow Dash headed for the door. Her sense of balance was still off, but she wasn't the best flier in all Equestria for nothing and easily accommodated the extra mass in her stuffed rump.

Choosing discretion, Rainbow landed on the large balcony of Twilight's castle and walked up to the door that led inside. Lifting a hoof, she started to knock when she felt the tentacles poke free of her rear again. "What now?"

One of them extended quite a bit behind her while another snaked around to her side. Rainbow tried her best to ignore all of them because with them out it meant her gut had a little break—though there was an odd sensation of something moving inside her still.

Twilight Sparkle, Princess of Friendship, opened the upper door of her castle and felt even better about her day. "Rainbow Dash! It's great to see you! Come in!" Without another word she turned and made room for Rainbow to come inside.

Wanting nothing more than to be out of the public eye, Rainbow Dash slipped inside as fast as she could—she didn't even notice one of the tentacles helpfully closing the door behind her. "Twilight, help! The tentacles have taken up residence again—well, they're probably not the same ones. I told them last time that if it happened again, I'm gonna charge rent or something." She was only half joking. After all, if they could understand her, they could gosh-darned work for their keep.

Freezing in place, Twilight turned around to look at her friend. It wasn't hard to spot the jiggling in Rainbow's belly, or the green tentacles that were waving about behind her. "Again?!"

"That water's really soothing, okay! I took precautions this time and everything!" Shivering at the feeling of something pushing around inside her, Rainbow turned her head. "Will you stop that?! I'm trying to talk!"

Twilight could only stare in shock as the three tentacles all seemed to calm down—one even retracting all the way inside Rainbow.

"Thank you. Now—" Rainbow Dash turned her head back to Twilight, "—I made sure to sit on my rump this time so they couldn't get in."

Now Twilight was a little intrigued. "But they got in anyway?"

"Y-Yeah. Can we not talk about that bit?"

When Rainbow stuttered her words, Twilight noticed something she'd missed earlier. "They got in your mouth, didn't they?"

Snapping her mouth closed, Rainbow slowly nodded her head. But she had to ask, "How'd you know?"

"Your tongue is green. It's a common sign of some of the rarer tentacle infestations that infect through the mouth." Twilight kept talking, but after her first four words, Rainbow was screaming. "Calm down!"

"But—"

"I have a book about this. Come along, and don't let your friends break anything." Twilight didn't need to know her castle backwards to be able to find the main library—she could sense such a large quantity of books.

"but…" Rainbow almost fell sideways at the latest squirming. It was pushing at things and places it had no right pushing at, and she wanted it to stop. "Please stop doing that. Look, I promise I'll find something tasty to eat later, would you like that?"

The squirming in Rainbow's belly stopped immediately. "Okay. We'll start with something sweet. Lots of sugar." The squirming was back, but it wasn't quite as purposeful as before. Rainbow could almost think of it as excited wiggling.

Realizing she'd been left behind, Rainbow flapped her wings and went searching for Twilight, only to find her in the main library of the Castle of Friendship. Twilight, Rainbow realized, was reading a book. "Okay, Twilight, when can you get rid of these wiggly things? I can't fly properly like this!"

Twilight didn't notice Rainbow. Reading through a book she hadn't touched in nearly a year had her full attention. When something bumped her, she jerked out of her reading-trance. "Huh? Oh! Tentacles. Well, reading through the latest copy of Wiggly Things and You, I think I've found what's inside you. They're called tentacalus infectus, there's two sub-species, but I'm pretty sure you've got this—"

"Enough of the egg-head talk. How do I get them out?!"

"Well, these tentacles are an endangered species. You have to wait until they move out on their own after they hibernate for the winter." Twilight was confused as to why Rainbow wasn't excited that they'd get to study such a unique creature. "Oh, but you're lucky it's not these other ones, they'll never come out once they get a host."

"Right, forget those then. So winter? It's just—We're in spring, Twilight." Rainbow Dash rolled her eyes and did the math. "So eight months like this?"

"Well, it's spring, so that means in a month or two it will begin laying eggs—that is, you'll begin laying its eggs. They really are quite invasive." Reading on, Twilight blew out a sigh of relief. "Lucky it's not one of the intelligent ones, though. Wow would that get problematic."

Rainbow Dash's blood ran cold. "Intelligent? How intelligent? What are you talking about?" When the tentacles in her squirmed, she turned her head. "I'm trying to work out how this is all going to go down. Can you please stop?"

Watching Rainbow's belly calm and the tentacles behind her still, Twilight gulped. "Uh, probably about that intelligent. I'll go get Fluttershy…" With each of the last four words, Twilight backed up a step.

"Wha—" Rainbow's tongue shot out of her mouth, and not just the little bit it should, she had nearly a quarter of a pony-length of tongue now, "Aaaaaaagh!"

Author's Note

So I do this "Ask X" thing. X can be any pony within the story. You can ask them anything and they will definitely, hopefully reply. Keep the questions appropriate to the age-rating of the stories, and they will answer the best question in the author notes of the next chapter. The more votes a comment has the more likely I will get it to the right pony to answer. Try to keep it to one question per post! They will pick one question per chapter.

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