Morning shone through the windows of the Crystal Castle, the warm sun waking up the Princess Of Love gently from her slumber. Opening her eyes slightly, she stretched out her arms, legs and wings and her body awakened slowly. She laid in bed for a few moments, embracing the day's sunshine fully and preparing for the upcoming responsibilities only a princess had to endure.

But before she moved, her stomach woke up and gave a small growl while waiting for its first meal.

“I hear you, you'll get your food soon. I just have to get up.” Cadance rotated onto her bottom and planted her feet into her slippers, riding the edge of the bed to gain some momentum into standing. Strangely, her body seemed to be weighing her down a bit, a little sway in her movement as he stood up. Along with it came an unusual sloshing from inside her, as if she had more tea last night than she remembered.

Okay… My body feels a little heavy and my stomach is sloshing around. I might have drank a little too much tea last night trying to get to sleep. Silly me.

Cadance chuckled to herself, moving over to her standing mirror to tidy up her mane and tail. But when she got to standing in front of the mirror… she saw something very different from what she was used to.

She gasped at the reflection she saw, almost stumbling at the sight. Her body had changed. It had gotten… bigger. Her legs were beefy and had fat in all places, her hips much wider than they had been before. Her face was chubby and her cheeks were rounded. But what she noticed the most were her breasts and belly. Removing her gown and revealing the purple lingerie she was wearing, she saw that her body was not only chubby… she was straight up fat!

Her breasts filled out her cups like ice cream on a waffle cone, pink fur overflowing in some places and her nipples visible at her tips. Her belly also was bigger, the biggest thing on her body. A gut rounder than a ripe melon pushed against her garter belt and poked out from under it, hugging the sides like a loose, but firm hug. She was fighting every urge to scream out in terror like Rarity would in this situation, but she managed to keep herself calm by using her breathing technique.

“W-what happened to me? I look… enormous.” She said to herself, analyzing her form in detail. She snapped the links in her legs and watched and the fat absorbed the impact, moving up to her hips and placing her hands on them. She saw that she was able to hold her whole hands up on them before they eventually rolled over to her Cutie Marks. That being said, her Cutie Marks stretched over her hips and even warped over her butt came into the picture.

Her tush swallowed the panties she wore entirely except for a little at the top, basically revealing everything she had and then some. Turning back around, she put her hands on her giant belly, rubbing it as she pressed in on her newly acquired pudge. Her gut felt heavy but soft, fuzzy but round, flabby but firm. Everything about her was now…

“Chubbylicious.” She said in an airy voice. Looking down, just to make sure she wasn't hallucinating, she grabbed her belly and squashed it in her hands.

All real… but what if…

Holding the sides, she wiggled it a bit and heard the sloshing from earlier becoming more noticeable. Letting go, it wiggled and moved for a few seconds before resting at its flabby position.

After doing that, her belly growled again. But it wasn't what she thought would happen. The surface of her belly visibly moved, the fat on her belly jiggling and bubbling along with it. Cadance watched as the layers of fat moved on their own, shifting her fat around before coming to rest soon after.

“Okay, let's set a few ground rules…” She started. “1: Overnight, I seem to have grown in size and weight. 2: My stomach sounds like a bubbling cauldron. 3: Said sounds are making my stomach move around like a loose jello mold. All things considered… Something went very wrong with something I ate last night.”

She racked her brain with possible culprits in this added weight from last night, recounting everything she did before she went to sleep. Then, her stomach piped up again.

“Oh hush you! I can't think of I can't hear anything!” She said harshly, her gut retorting with just as violent a comeback. Perhaps her gut was having a bad reaction to the herbs? Could she cure it? Or maybe, this was a sign of something bigger.

“Maybe… This is a sign from my inner subconscious. I was talking about how I couldn't possibly enjoy or find satisfaction in having a bigger figure yesterday. Perhaps my magic did this to me and this is my own way of testing the waters.” Her belly gurgled in response, almost as if it was encouraging her to explore. Shining Armor and Flurry Heart were off on a Daddy/Daughter trip for the next few days, so the castle would be all to herself.

“Okay then, let's see what exactly I'm dealing with here.” Cadance declared. Walking back from the mirror to get a full picture, she went about feeling her belly over.

She felt it over and noticed it had two layers. A smaller top layer that was more firm and a bottom layer that was all squish. Clearly, she had a double belly, her belly button smushed between the two and deepened to a degree that would make it look like a pit made out of pure darkness.

She touched the surface lightly and felt how malleable it was, easily moving around her finger and swirling the fat. Lowering the garter belt of her lingerie, she slapped the blob and watched it jiggle. Waves careened over her belly, starting at her belly button and pulsing out and across like a central nerve sending signals.

“Wow, it's like my belly is acting like Whinny the Pooh-ny’s belly from the childrens books. Wiggling and swirling around…” Cadence chuckled a bit. She actually started enjoying the sight. Just then, her belly growled, stuttering and shaking the fat on it. The blob jiggled and jumped around, almost cartoonishly so. This continued for a few more seconds until something else happened…

Pop!

Her belly grew larger. Cadance was surprised, her belly was just a little smaller before, but was now wider and bigger than before. It had more volume, the double layers were gone and most importantly… She felt good about it. It was hard to explain, but she actually felt rather aroused by the sight, sound and feel of her plump figure. Everything down to the last drop of fat on her body seemed to turn her on. And it made her want to take it further.

“Well, this is… interesting. I wake up after talking down about the idea of having a plump figure, I get said figure and now, I'm turned on by it. Maybe I should push this to the next level?” She said, a newfound confidence riding up her spine. With said confidence, she decided to share this new endeavor with three other big ponies she knew. Grabbing three pieces of parchment and writing on them at the same time, she sent three invitations to her castle to share what she now wanted to embrace. The hypnotic feel of her noisy body.

–

Later on, in the Crystal Castle…

Cadance sat in wait for her guests to arrive, snacks and drinks set in place around a circle of fluffy cushions to sit on. Cadance patiently watched the clock tick by, feeling her massive form over and over as she sat there in both curiosity and now a new sense of intrigue. Despite the larger than life wake-up call, she soon grew more comfortable with the prospect of her form gaining a few pounds, the slim figure of her princess body being replaced with a soft, wiggly fat that moved around on its own.

Speaking of moving, without anyone to ‘Seduce’ with sound, her belly idly moaned and groaned, the occasional lurch or bubble disturbing the surface. Soon enough, her first guest arrived in a blue flash of magic. Her Auntie Luna came dressed in a purple dress that covered her entire body, flowing with sparkles and patterns of constellations. But one thing that stuck out was her bulging belly in the middle.

Recently, Luna found the time to indulge herself in the modern sweets and other foods of today's age, taking no offense to her own larger body becoming more and more noticeable. Sitting down on one of the cushions with her legs crossed, she addressed her niece.

“So… would you like to explain the rather confusing nature of your message? Not that it wasn't interesting, is all.” Luna asked.

“Well, it's sort of hard to really wrap my head around it. When I woke up this morning, I woke up to this.” Cadance lifted the front part of her dress and revealed her large belly, an accompanying gurgle to go along with it. This surprised Luna to a decent degree, her sight locked on her niece's plump pouch.

“Interesting… it seems your stomach has grown significantly overnight.” The lunar goddess said.

“I know, but that's not the weird part. The weird part is the fact that everytime it growls or makes any noise, I seem to be turned on by it. I suppose this should be no surprise considering what my prevailing theory is.” Cadance explained.

“Hmmm… and what would that theory be?” Luna asked.

“I was talking to Twilight and some of her friends about the usual romance topics when Rarity brought up the fact that girls with big, noisy bellies seemed to be the big craze for guys and personal pleasure. Fluttershy said that she was gaining and Twilight herself said I could use ‘Some meat on my bones’ and that I might like it too. I got sheepish and denied the fact before I decided to head home. Later on, I found this pretty blue flower that smelled wonderful as I was making a slight detour through a forest path and I decided to take it home for my evening tea. After making the tea, it seemed to bubble without a heat source to warm it.”

“I ignored it and heated the liquid up to temperature before drinking it and heading to bed. Then, this morning, I woke up and found my body to be extremely plump and my belly to be more noisy than a brass band in highschool. My theory is that my magic enhanced my tea to give me this body as a sort of karma for how I reacted, a subconscious act to show me that I might be wrong.” Luna hummed to herself as she thought about her niece's words.

An odd amount of fat gained overnight and a feeling of arousal when presented with the noises of her stomach? That doesn't sound like magic…

“Cadance, you said you used a blue flower for your tea last night, correct?” Cadance nodded. “Did this flower have petals both sticking up and drooping in a star-like arrangement? Small blue pollen buds sticking out of the center and a faint glow?”

Cadance nodded again. From that silent answer, Luna knew exactly what she had ingested. “Cadance, I believe I know what has happened to you. And it doesn't involve your magic.”

“Really? What is it?” Before Luna could speak about what she had to drink that night, the second guest walked in. The Princess of the Sun herself, Celestia waltzed in with a bathing suit on. It was a bright red with swirls and circles adorning the fabric with a net at the center that showed off her cleavage, her top barely being able to hold her much more hefty breasts. Her butt was no different, the red bottoms being much more visible, but still getting swallowed whole. And her belly was much to show for.

A white blimp hanging over her thighs but still maintaining a sort of rounded oval shape while sagging. Sitting down opposite of her niece, she greeted her sister and began speaking.

“Cadance, so good to see you again. I see that you've become much more rounded since I last saw you.” Celestia chuckled. Cadance rolled her eyes.

“Very funny, Auntie, but this isn't exactly what I'd consider a social call. Well, not entirely at least. Think of this as a get together/experiment.” She spoke.

“How so?” Celestia asked. Luna told her the mean and mode of why they had been summoned and Celestia had to concur with the theory she presented as to why Cadance was experiencing these new abilities.

“I must agree with my sister. What you are experiencing goes beyond the realm of magic. It sounds much like a plant we've both had to deal with in the past. Poison Joke.” She said sternly.

“Poison Joke?” Cadance parroted in confusion.

“A plant only found to grow in the Everfree Forest on the outskirts of Ponyville. The plant you speak of using as an herb has a tendency to turn ponies into much… different creatures. The pollen of the blue flower has been the only way that's been recorded to have a lasting effect.” Luna said.

“Poison Joke is an interesting thing. As the name suggests, the flower’s effects cause adverse reactions that would only be described as something straight out of a practical joke book. Twilight and her friends experienced the effects first hoof when their zebra friend first made her appearance in the small town, the effects ranging from an enlarged tongue to a deepened voice and even unkempt fur that resembled the coats of a yak. And like my sister has said, only the pollen the flower excretes when in proximity of another creature has ever been documented. But from what you have said, you went a step further and ingested it.” Celestia added.

“So that's why I felt so odd today. And it explains the odd… changes I've been going through. Has there ever been any other reports of ponies ingesting Poison Joke and the aftermath?” Cadance asked, the blue alicorn shaking her head.

“Unfortunately no, there has not been anything reported related to how you took on the strange properties of the Poison Joke’s effects. There have only been theories of what could happen after eating the flower, but in terms of documentation, you'd be the first case.” Luna said as the third and final guest appeared from the hall, surprising the Royal Sisters. The last guest to arrive to the occasion, sporting a thong and bra in a lime green shade was actually Fluttershy.

Her body was much like Celestia's, but her belly was much bigger. Her belly was a large bubble of yellow mass, lines moving from her belly button and across her belly that faintly gave the shape of three sections of fat. Her cups were also large, the bra she wore only barely covering up her nipples and revealing everything else to see of her yellow orbs. Sitting down with her legs in front of her, the princesses greeted her.

“Fluttershy, good to see you. It's been too long since we've talked. How are you?” Celestia asked.

“Good, thank you. I know I'm usually the sheepish one in my friend group, but when a friend asks me to come over to, quote ‘Feel comfortable in our own fat’, I won't turn it down.” Fluttershy said, twirling her mane on one finger.

“Well, it's good to see you here with us today.” Luna said, turning back to Cadance. “So, my dear niece, how shall this get together work?”

“Well, I was initially going to test this on my own. But, I decided that it wouldn't be useful to just do this alone. Perhaps, in some odd way, this isn't just exclusive to the Poison Joke and we all can find pleasure with all of our larger than life bellies. So, I gathered some of the best snacks, drinks and a few potions of Borborygmus to ignite the flames within us.” Cadance said, a much more confident tone of voice.

“Borborygmus? That's a funny word. What does it mean?” The yellow pegasus asked.

“It's the scientific term for the sound your stomach makes when you're hungry. But society chooses to use more simple words to describe the audible discharge of your midsection’s motion. And with these potions, they will induce that noise artificially to test the waters.” Luna explained.

“This seems strange, even got you, my niece. Why do you want us to partake in this?” Celestia asked.

“For all the romantic things I suggest to other ponies in my court when they ask me for advice, I suppose now would be a time to take that same advice and apply it to this. I will admit, I am slightly.. turned on by the sounds of my body. And I would like you all to take this on with me as a sort of.. experiment to see if you all have the same reaction.”

“Well, I've never been a fan of potions, but I'll give it a go!” Fluttershy declared.

“Then it's settled. Ladies… let's make some noise. First, let's get some food in us to add a base.” The group then grabbed from the snack pile and took to their eating montage. Bags of chips, gummy bears, bowls of chili and soda disappeared into the bellies of the ponies. Gulp after gulp, a good portion of the snacks were sampled and swallowed.

“Okay, now you three use the potions to get your stomachs started. I have the natural advantage already, but I may choose to use it when needed.” Cadance said, the other three guests nodding as they popped the corks off the bottles and chugged them all down until the liquid within them was gone. Placing the bottles on the table they all leaned back and let out a sigh. Luna revealed her perfect ball of a belly as she lifted up her dress while Celestia and Fluttershy held the sides of theirs as they let the potions settle.

“Okay, here we go. Let's see what we've got.” Silence came over the room for a few seconds, the idle air swirling around them as they all waited for the first sound of the symphony to begin. Soon enough, Cadance heard her belly start with a warbled gurgle that echoed through the room, strange bubbling adding to it as the pink ball bellowed.

“Ooh, you were right. Your stomach is really loud…” Fluttershy said, looking on as the pink blubber of Cadance's middle visibly moved

“I told you. She's been very talkative all day today. I'm starting to think it has a mind of its own.” Cadance said.

“I see. I suppose this comes from the Poison Joke in your system radiating out into the world. Curious how it doesn't affect us at all.” Celestia said. Then, the sound of growling bellowed from her insides instead of Cadance's. Her belly growled like a mad beast, the snarling reaching critical mass and shaking her gut before going silent.

“I'm impressed, dear sister. Never have I ever heard your bowels emit such a sound so close to a Manticore.” Luna teased.

“Oh don't start, Lulu. You have just as much of a brass band in your belly as I do, so don't act like you don't have your moments.” At that moment, Fluttershy's gut gained its voice and began a roar of rumbles that shocked the rest of them. Her yellow gut shook and shuddered under the pressure of the potion, the rumbling making her belly look more and more deformed as it moved and jiggled.

BRRRRRRBRBRBBRBBRRRRRRRRUMMMMMMMMMMBURURUURURURUUUUUUUUUUURB!

“Goodness! I haven't heard that much noise come out of my body since I started this gaining thing. That potion must be strong for it to have this type of effect.” Fluttershy exclaimed, holding her belly still.

“I have to admit, a sound of that magnitude coming from you? That is a true surprise. I always knew the shy ones had the loudest moments when the time came to it.” Luna added, soon remembering her own commitment to the challenge as her belly began to sing.

Ripples of fat rolled over her belly, a deep moan bellowing through her innards. Bubbles and gurgles soon followed as the potion worked its magic on her with a loud signature.

“Well, it seems all of the potions have begun to take effect. Now it's time to join together and embrace our new forms.” Cadance moved the table over and allowed them to have some more room. Gurgles rose up from below and rattled her belly even more, as if responding to the added noise of her guests’ own outbursts.

“Ooh, that's a big one. What's wrong, my sweet? Feeling a little bubbly?” Cadence's belly responded by roaring with an up and down wiggle, as if nodding to her.

“It seems like your insides have a mind of their own. Perhaps we all have a little personality within our bowels in some way.” Celestia said. Her belly lurched at the sound of her voice and gurgled its own response.

“It seems we all have a different inner voice within our loud bowels. Personally, I think this might turn into a new pleasure for many a mare from this day on.” Luna suggested, rubbing her midsection.

“Actually Luna, it already has.” Fluttershy passed a newspaper article to the blue alicorn. “It's already becoming a thing to listen to your belly by yourself or with friends for pleasure. They're calling these get-togethers ‘Belly Bashes’.”

“Interesting. Perhaps this little Poison Joke accident can be turned into something entertaining? Maybe I could add more to this experience and have other ponies join me here over the next few days to do so.” Cadance scratched her chin in thought. This little incident has led her to find a brand new interest, or in this case, a developing kink that she was increasingly becoming fond of.

“Now I'm getting new ideas! And one of them just came to me.” Cadance said. “Let's go two on two, belly to belly.”

“An interesting concept. Fluttershy, would you join with me?” Luna asked. The yellow pegasus nodded and scooted over to her, pressing her belly to hers. The heat from their bodies melded nicely, the feeling of the direct contact satisfying them both. Cadance and Celestia also went along with the idea, their smaller guts coming together as well.

With the four ponies now teaming up with one another, they waited for their next noise bombs to be dropped into their bellies. Luna and Fluttershy would be the first to take to the stage as Luna's gut roared with Fluttershy's and created an even bigger noise.

Brrrrrrerrrrrrrrrourrrrrorrrup…

The other two princesses weren't too far behind as their joined tummy tango echoed through the room.

Grrrrrrourgerrrrrrrrrrourrooooo…

Both pairs let their guys ring out as teams, almost like they were battling to see who had the most in them when it came to noise. Just before anything could go further, Cadance's belly began to bubble on its own. She pulled away from her eldest aunt and watched the surface roll and move.

Celestia, Fluttershy and Luna also noticed their guts began to howl, like a pack of Timberwolves was on the hunt. Each one of them felt the roar of the internal turmoil twist their insides and just about stopped all other thoughts in their minds. The sound of their bellies were so powerful that it was almost like they were hypnotized into listening. The three guests stopped their guts from going overboard, but Cadance let hers continue.

“Y'know, I've come to accept what this Poison Joke has done to me. And I have come to the conclusion that I will continue down this road and test it with others. This will be a strange thing to get used to, but I have full faith that I will prevail.” Cadance declared, getting all approving nods as she made her list to continue this little caper of hers into the next group she'd come to meet. Her and her noisy insides.

Author's Note

There we go! I finally managed to get this done. Took me a while to work out some of the kinks (No pun intended), but I got it done and that's all that matters. Looks like Cadance has found a new pleasure to pursue. Will she find more ponies to bond with over their bellies? Find out next time on the next chapter of: Hypno-Tummy!