Shutters closed? Check. House empty? Check. Driveway empty?
This time Mary was playing it safe: her parents had left on their week-long honeymoon yesterday, and she'd managed to earn just enough brownie points with her parents to not warrant a house-sitter. The driveway was, and would be for some time, empty. She was still grounded for breaking the fire extinguisher a few weeks back, but that wasn't going to stop an aspiring engineer! Or, rather, a Do-It-Yourself enthusiast. She never got to make that dry ice icecream she wanted, but with the new fire extinguisher under a combination lock, no amount of DIY lockpicking videos were going to help at this point, so Mary promised to set her sites on grander (and hopefully tamer) pastures for now.
 
She groggily rifled through the kitchen after waking, not for anything nefarious like last time but for breakfast and, to a lesser extent, for inspiration for her next project. Her beloved onesie pajamas were still in tatters from the fire extinguisher incident, so she was forced to settle for sweatpants and a hoodie as her next-comfiest outfit-- a bitter but necessary compromise. As her hand shuffled through old cereal and cracker boxes, it bumped into a stack of something in the far back, and the clattering of small cardboard boxes caught her attention. Stepping on a chair to get a better look, Mary discovered she'd knocked over a large stack of old jell-o mix boxes, taking up the entire back section of the cupboard. She pulled one out to give it a look-see. How long had they had this? Evidently long enough for the 'Best if Used By' date to have passed years ago. Jeez, these things must be as old as she was.
 
Well, the sweeteners might have gone bad, but there was no sense in letting perfectly good gelatin go to waste! Mary reached to the back of the cupboard, pulling out the largest armful of old boxes she could while her mind raced over all the wonderful things one could make with gelatin. Oh, she could make oobleck! That non-Newtonian fluid with all those weird properties...
...except making oobleck was the DIY equivalent of 'Baby's First Science Project,' and she'd already made plenty of the stuff in the past. She knew she promised herself something more tame than the last project this time, but she had to set standards somewhere.
 
Mary piled more of the boxes onto the kitchen table, letting her mind wander as she began to tear them open and separate out the little packets of gelatin powder. It could be used to make industrial-strength bubbles, but she'd already done that before. She could...use it to make cheesecake? Wait, that wasn't a project, that was just cooking. Gelatin was neat stuff, but she was just at a loss of what to do with it. Mary stared across the kitchen in thought and her eyes landed on the family beach photo plastered to the fridge. She frowned as she realized her chest still hadn't grown out of that green swimsuit she had bought years ago when her boobs were just starting to come in. Bah, she didn't need a swimsuit figure. She hadn't worn that thing since the first time she tried (and failed) to make polymer balls in the bathtub...
 
...hey, that wasn't a bad idea! She never actually got to make those water gel balls, truth-be-told. She might as well use all this gelatin to one-up her past self, if she couldn't think of anything better. Mary swept the boxes of useless jell-o mix into the trash, escaping to her room with an armful of powdered treasure and a smile.
The guide was pretty straightforward. Gelatin powder, water, dish soap, a couple other ingredients, mix while hot and put it into water balloons to leave in the fridge overnight. Easy-peasy, if boring. Mary's impatience (the culprit of her last failure) got the better of her, however, and she kept adding ingredients to the mix in an attempt to make it harden faster. Eventually patience was the victor, as her experimentation proved for naught. With a tinge of disappointment, Mary set the water balloons to rest overnight, having to use the giant cooler in the garage as she'd accidentally made far too many to fit in the fridge.
 
The next morning started off droll, and it took until Mary was halfway through a bowl of cereal before she remembered she had left a project to cool. She dashed through the house and into the garage, scavenging a bucket and some scissors. Surely enough, upon opening the cooler, it seemed the gelatin had set! And shrunk too, judging by how deflated each of the water balloons looked. She paid it no mind, cutting each of the beads free from its rubber prison and dropping them into the bucket. It was a long process to empty them until the bucket was full, but thankfully only a fraction of the time it took to make them. Mary picked up one of the little gel balls out of curiosity for her work.
 
For all intents and purposes, it seemed like she was holding a clear glass marble that had been left in the cold. She rolled it in her hand to warm it up, and sure enough eventually the outer layer thawed enough to feel the jelly-like exterior. Mary fist-pumped and dropped the bead back into the bucket, congratulating herself for already doing better than her last attempt. All she needed now was a place to put them to the test...and this time, she already had a lab prepared!
 
Lugging her bucket of beads with her, Mary made her way out the back door of the house, and onto the stone patio that would serve as her testing ground. Though it was technically outside, her dad had built curtain walls around the edge of the area to ward off bugs at night, giving it the appearance of a large cloth tent. And in the center was a kiddie pool, already inflated -Mary patted herself on the back for preparing it ahead of time- and ready to fill. Without a word, Mary unceremoniously dumped the contents of the bucket into the still-empty pool, watching the beads bounce and spread to nearly coat the floor of it.
 
The next part was easy: water. Mary tugged at the length of hose nearby and set the end of it into the kiddie pool, turning the nozzle to a low, steady stream. The gel beads swirled with the meager current, giving the impression of a shallow whirlpool, before the water level rose just high enough to submerge all of them. And like that, they were gone! Invisible, their index of refraction the same as the water that surrounded them.
"...huh. Maybe I should have dyed them," Mary commented aloud, slightly disappointed, "Well, whatever."
 
She crouched down to watch her creations as best as she could, only being able to see the occasional ripple or bump as one of the gel beads was pushed out of the water slightly by the current. She occasionally took out one or two to test if they'd gotten bigger, her impatience once again getting the best of her, and after ten minutes she came to the decision that this was really, really boring. She retreated back inside to let her latest project stew.
 
A few minutes later, she returned, this time in the green two-piece swimsuit from the family beach photo, and with her laptop in tow. She figured as long as she was going to sit here and watch disappointing marbles grow, she might as well relax while she did it. Her figure wasn't anything to blow guys away by any stretch of the imagination, and her small breasts hardly flattered the two-piece suit, but at least she was thin. Miraculously her escapades from a few weeks ago hadn't earned her any permanent stretch-marks, which she was thankful for not having to explain to her parents. She took one tentative step into the kiddie pool, the feeling of gel-beads under her nearly causing her to lose balance, but Mary eventually found purchase in the cool, shallow water, and sat down at the edge of the pool with the hose in hand, setting her laptop to play some tunes from atop a chair.
 
The sensation of the polymer balls in the water was strangely...absent. While the water was still, she couldn't discern if there was anything in there but water, but sweeping the hose across the pool pushed them around again and she could feel them bouncing and sloshing around her. At this low water pressure the kiddie pool's level was barely up to her mid-thigh, but she had nothing but time to waste. She absentmindedly swished the hose around the pool, until she mistakenly ran it between her legs, eliciting a small inhale as the tiniest bit of cool water squirted into her backside. All at once, the memories of the fire extinguisher incident came back.
 
She supposed it hadn't been...the worst experience. She was lucky to get off with nothing but a grounding, and her parents never found out exactly where that extinguisher nozzle ended up. And it had certainly given her something to think about! And a whole lot of weird dreams. But Mary had sworn off any hoses in that area, fearing she wouldn't be so lucky the second time. But...she supposed so long as the hose didn't actually go in, there wouldn't be any harm...
 
Her curiosity getting the better of her, Mary spread her legs in the pool, put a thumb over the end of the hose to increase the pressure, and pointed it towards her backside underwater. The flow of cool water there felt...nice, actually. As she relaxed her butt, a little bit of water squirted in again. Putting the hose slightly closer, the flow inside increased, and she could feel a small amount of pressure building up inside. Having the situation under control this time, Mary pushed out, emptying the clear water back out into the kiddie pool and eliciting a relaxed sigh.
 
She continued this process, always sure never to actually put the hose inside, but just close enough that the current could push water into and out of her bowels. Eventually she let the pressure build up until her belly had a sizeable bump, like the pot-belly she'd worried about a few weeks back. Feeling in control this time, she pushed down on the bulge, finding some entertainment in watching her stomach rise and fall as the cool water reached further and further inside. This wasn't so bad when she didn't have a one-way hose lodged in her.
 
Unbeknownst to Mary, however, the number of invisible polymer balls in the kiddie pool was slowly dwindling. Swept up in the current leading into her backside, the tiny gel-beads one-by-one popped inside of her along with the flow of water, while only water was getting pushed out. Eventually less than half of the original bucket remained, invisibly swirling around Mary in the pool.
 
Mary frowned as she found herself, at one point, unable to get rid of the last bit of water inside of her, a tiny bulge remaining when usually it would become flat at this point. She figured her guts had finally decided to close the waterpark, shut the doors and wait for whatever water remained to be absorbed. With her newest source of entertainment cut off, she let the hose sit to the side while she leaned forward to inspect one of the water beads. With the water level now just below her chest, she figured about an hour had passed, and a look to her laptop confirmed that guess. She moved her hands around in the pool for a few seconds, wondering that there were supposed to be more of them, before finally nabbing one out of the water. She held it to her eye, and huffed.
"...aw, man. Not even a little bigger?"
So much for one-upping her past self. She still couldn't get the recipe for these little suckers right! She tossed the overrated marble back into the water, and exhaled in defeat. So much wasted gelatin. She should've just made oobleck. Mary leaned back and let the tunes from her laptop console her, feeling like she'd wasted a whole two days on this dumb little project. She leaned over to turn the hose nozzle off, not feeling much of a point in it anymore, and let herself wallow in her kiddie pool of shame.
 
---
 
Mary was snapped out of her nodding off by the sudden sound of a splash, unsure of how much time had passed. A quick look to her computer said thirty-or-so minutes. She scanned the water for the source of the noise, and found an odd sight: one of the polymer balls was now floating halfway atop the water instead of underneath it. And more importantly than that, it was nearly the size of a baseball! She picked up the rubbery ball with wonder, feeling its gel-like texture under her hands and marveling at all the tiny bubbles inside that gave it a whiter coloration than it was originally. Then, another splash, as a second gel-bead shot out of the water slightly before plopping back down, looking the same as the first one. She picked it up too, putting them next to each other. A third shot to the top of the water beside her, and then a fourth.
"...I...it works!" she squealed, a smile creeping onto her face as she reached forward for the new balls, "They actually-"
 
A beat ran through her whole body, forcing her to stop cold. It felt like a heartbeat, but more intense. And it came from her stomach. A fifth polymer ball shot to the top of the water beside her, followed by a sixth and seventh, growing steadily more sporadic, and then another thud rocked her body. Mary looked down-- sure enough, two almost imperceptible lumps dotted her gut. A third joined them a moment after, causing her to inhale sharply with the sudden pressure.
 
There was a moment of silence as realization dawned on Mary.
 
"Oh no."
 
As if they'd been waiting for her cue, the kiddie pool suddenly became alive, churning and splashing as new gel-beads suddenly expanded and rushed to the surface like popcorn. At the same time, the thuds and beats in Mary's guts became more sporadic. She put her arms around her stomach in discomfort, pushing with all of her strength to get them out before the worst occurred, but to no avail as the polymer balls were too big to push out. She felt them multiply under her skin, her bowels shifting and churning to adjust itself to all of the new objects pushing against each other inside. They pushed back against her arms, her belly lurching outward in periodic spurts as more of the polymer balls inside reached their full size.
 
The competition for room was fierce, and Mary cried out as more and more of the expanding gel-beads pushed each other deeper inside, finding no exit in the usual place. Her stomach was the size of a nine-month pregnant woman, but the bulging lumps exposed what was really inside her-- and it showed no signs of stopping. She tried to flip herself over to crawl out of the pool, but the sudden shift in weight pulled down on her guts, creating more room for the beads to fit into. She pulled herself halfway out of the pool, her bloated stomach dragging along the floor, all while the kiddie pool itself still splashed with newly-grown beads of its own.
 
Every movement Mary made shifted her guts around, either pushing more of the polymer balls deeper inside of her or creating new room to fill. Her skin pulled tight as the beads continued their assault on her churning guts, more plainly revealing the shifting mass of growing gel beads. Soon she was unable to even stand up, the sheer weight of the eggs inside her mixed with her dwindling strength proving too much to overcome. Grossly distended and at the mercy of the polymer balls inside her, Mary could only let herself fall forward, somewhat propped up by her midsection. Her guts whined in defiance at the new weight, and she moaned as the pressure doubled, pushing the orbs further inside her in search for room.
 
---
 
Mary couldn't tell how much time had passed, but the flow of new beads had mostly slowed to a stop. She couldn't see her laptop from this angle, but it kept humming its jaunty tune, so at least it hadn't run out of battery. There was no hope of wrapping her arms around her belly anymore. She couldn't have been much bigger than the fire extinguisher incident, but the balls inside her were heavy, and infinitely more solid than air, so every new bit of volume made her stomach rumble and churn in objection.
 
She looked like she was balancing on a yoga ball filled with bean-bags. Every now and then a new bead would find the gumption to pop into its full size, eliciting a groan from the girl as the ripple of movement ran across her bumpy skin. Unlike the fire extinguisher accident, however, there was a new kind of pressure that had been building up she didn't recognize. It was further down than her bowels, the immense weight pushing down on one of her other organs, and though it took her a while to realize it, she liked that. A lot. All this weight down there was doing something to her nether regions.
 
Another bump rocked her body.
"Ahn..."
 
Another.
"Mmg!"
Something she'd never experienced before was building up, and she wanted to let it finish.
 
And then, it stopped. The bumps stopped coming, and she balanced precariously atop her own guts for a few minutes in silence before realizing nothing was going to happen. She was grateful the nightmare had finally stopped, but a small part of her was disappointed. Nevertheless, the sun was beginning to set, and even though her parents wouldn't be home for several days she couldn't stay on the patio all night. With a grunt of effort, she mustered all of her strength into pushing off the floor to roll off of her stomach into a sitting position-
 
-and all at once, the remaining beads took the opportunity to take advantage of the new room, popping into their full size in rapid fire. Mary's stomach churned loudly and lurched forward, she could see the bumps moving beneath her taut skin in quick succession, and the new weight pushed down on her nether regions to an unbearable degree. She quickly wrapped her arms around the sides of her belly as all of the heat built up at once, and she cried out as the last of her strength left her.
 
Breathing hard, Mary fell to her side and let unconsciousness take her.