Chapter 1

“Diaper baby!” Vanellope said, sticking her tongue out as she moved her pieces “Are you even trying?”

“I’m just not good at games like this.” Ariel sighed “Ugh, I give up.”

“Yes!” Vanellope said “Hey thanks for letting me hang out with you girls. Ralph is fun, but I need some girl time, you know?”

“No problem!” Belle said, ruffling her hair “Any princess is welcome with us!”

“There is something I was wondering.” Jasmine asked “Why do you call people ‘diaper baby?’ Aren’t you older than that?”

“Oh.” Vanellope blushed. She didn’t like talking about her backstory too much “You know how game characters get programmed backstories? Mine is that I’m seven, but was in diapers until two months ago. I needed to potty train to become princess.”

“Wait, so you remember wearing diapers?”

“I, um, still technically do. At night.” Vanellope said “Pull-ups I mean. But baby diapers? Yeah, I’ve got lots of memories with one of those bulky things on. Lots of memories um… using them too.”

“Oooh!” Belle said “What’s it feel like to poop in a diaper?”

Vanellope blushed. These princesses really needed someone to explain normal social ettique to them.

“Well, I mean I always noticed a smell first.” She said “Like I would wonder what stank. I often thought it was another baby, there were a lot of babies around me, but then I’d accidentally squish my diaper and I’d realize that I’d pooped myself.”

“So you don’t even realize it’s coming out?” Belle asked in fascination

“Not really.” Vanellope “Not until you’re pretty far along in potty training. Before that it kind of just happens, maybe you fart loud enough for you to hear but usually it takes some time to notice. You’re walking along after dinner and suddenly you realize you have a mess in your pants. But that’s what diapers are for. And adults, adults notice right away for obvious reasons.”

“Aww!” Belle gushed “Oh I so would change your diapers if you ever wanted to be a baby again!”

“No.” Vanellope said firmly. She stopped. There was an all-too-familiar stink wafting through the air. Ariel and Jasmine looked straight at her.

“It’s not me!” She said indignantly, putting her hands on her hips. She subtly tugged on her underwear to make sure. Yeah, she wasn’t squishy.

Jasmine gave her a skeptical look and Vanellope flipped up her skirt, showing off her lollipop printed underwear. Yes they were a little thick in front to absorb any stray dribbles from her bladder, but it wasn’t a diaper and she wanted to dispel any doubt that she had just pooped. Ariel frowned. It was hard to argue with that.

“What’s wiff da funny wooks?” Belle asked, looking around

Vanellope’s eyes went straight to Belle’s butt. She was adept at spotting the outline of a diaper under clothes and… there was no doubt that Belle was heavily padded. Wait, but had she always been? Surely if she pooped herself frequently then they would have noticed before!

“Oh, I smewls someting stinky.” Belle said, looking at Vanellope “You needs a changie?”

Poof! Her long dress vanished, leaving her in a short, yellow skirt. It was pretty unambiguous. Poking out underneath was a rose printed diaper, brown stained in back and yellow in front. Belle was utterly oblivious, playfully poking at Vanellope’s skirt. 

“Belle...” Ariel said, unsure of how to tell her friend

“I wants cuddles!” Belle suddenly declared, diving into Vanellope’s arms. Vanellope wobbled, only to realize with a start that she could hold Belle’s weight. Not just that, she could hold Belle pretty easily. The princess was getting smaller, and younger. Suddenly Vanellope was holding a two year old sucking on a pacifier and wearing a very recognizable yellow dress.

“Mmmrph!” Belle grunted. Faaart! Her diaper expanded in Vanellope’s arms as she relieved herself.

“Oh, I made poopy!” She grinned, clinging close to Vanellope even as she tried to hold Belle and her stinking tush away from her face.

“You just noticed?” Vanellope asked “Wait, what happened to the room?”

The lounge was gone, replaced with what could only be described as a nursery fit for baby princesses. Dozens of changing tables, cribs, and high chairs were dotted around, with the ground covered in baby toys, blankets, and stuffed animals. Bouncers lined the baby block printed walls and full bottles were scattered about. There seemed to be no end to things that babies would like.

“What’s wrong with Cinderella?” Rapunzel asked from across the room. She was holding a small, blonde baby girl in a light blue onesie and a baby bonnet. The baby girl giggled and made a face. Vanellope didn’t hear the farting, but she saw the seat of Cinderella’s onesie bulge out.

“Oh my God she just pooped!” Rapunzel said “Cinderella’s a baby in a poopy diaper!”

“Okay everyone, don’t panic.” Vanellope said, hastily opening the game’s source code. She couldn’t necessarily edit anything from here, but she might get a sense of what was going on “It looks like we’ve been transferred to a game called… Disney Princess Nursery?”

“What kind of game is it?” Jasmine asked, looking between her legs. Something was feeling a little bulky down there.

“What kind of game do you think?” Vanellope asked “You have Disney Princess Babies in a nursery. You pick one and take care of her.”

“Which means…?” Jasmine asked, trying to hide the warm wetness spreading across the front of her diaper.

“You get fed, you nap, you poop, you get changed, repeat.” Vanellope said “Eventually the player can potty train you, after which point the whole process starts over.”

“Oh. So I… I...” Jasmine suddenly found herself shrinking. She toddled over to Vanellope’s leg and held on “I no wanna be baby!”

Splllart! Vanellope held her nose as Jasmine’s play shorts drooped. She set Belle down next to her.

“Why does everyone feel the need to mess their diapers around me?” She asked “Go play somewhere else.”

“Bud I’s nodda… nodda...”

Poof! An orange cat appeared next to Jasmine, instantly taking her attention.

“Kitty!” She squealed with delight, running over to hug her favorite pet, no longer caring about her big, sagging diaper.

“Wait, so did you say the instant we graduate to underwear we get reset to diapers?” Ariel asked

“Well yeah.” Vanellope said “That’s the way these kinds of games usually work. Let’s see here… You get a gold star next to the princess’s name for each time you potty train her. Each subsequent potty trainings is harder, she’s more likely to become stubborn or develop a fear of the potty. Earning the fifth and final gold star for each princess takes weeks of dedicated care, attention, and love.”

“But they could keep us right before that, couldn’t they? Like permanently in pull-ups?” Rapunzel asked

Vanellope couldn’t believe that she was actually hearing one of the princesses trying to negotiate for pull-up privileges. 

“Doesn’t work.” She said “You relapse to diapers if your caretaker tries to pause your potty training or doesn’t check in often enough. The only exception is Ariel, she defaults to pull-ups.”

“That’s not fair!” Rapunzel complained 

“So I, um, just wet?” Ariel asked

“You wet and cry a lot.” Vanellope “I think they’re going for a water design for you.”

“Oh well I guess that… that’s not gonna be so bad...”

Ariel closed her eyes and tried to put on a brave face as she felt herself pixilate and compress. The others looked on, powerless to help their friend as she was reconstructed as a toddler, maybe 4 years old, in a one piece swimsuit and water wings. Her swim pull-up was easily visible through the thin cloth of her bathing suit. She made a face and a box with a water faucet popped up in front of her, pointing straight at her diaper. She toddled to a screen that materialized in front of her.

“Oh, looks like Ariel is the first to get adopted.” Vanellope said “The game must just be prepping the rest of us.”

“Hi Daddy!” She said, cheerfully bouncing up and down “Want to play with me?”

A high chair materialized next to her and a disembodied hand picked her up and plopped her in. A jar of baby food with the word PRUNES on the front appeared in front of her.

“Um, Daddy, you should only use prunes when you need a baby to do stinkies.” Ariel chirped up “I’d like mac and cheese please!”

The hand ignored her, materialized a spoon, and scooped up a giant mass of mush, and pushed it straight into Ariel’s mouth.

“W-What’s he doing to her?” Mulan asked as Ariel was stuffed full of mashed prunes. Her tummy gurgled

“D-Daddy!” Ariel said, holding her tummy as she took another spoonful “I can’t hold it!”

“Yeah, looks like there’s a bonus unlockable for unpotty training Ariel until she gets the ‘mudbutt’ characteristic.” Vanellope said, flipping through Ariel’s book “It makes sense that someone would go for that in the early game.”

“Daddy!” Ariel shouted one last warning before her bowels gave way. Blllartch! Her pull up stained brown and stretched underneath her swimsuit, not meant to take a full mess. Ariel’s bottom lip trembled.

“Whaaa! Daddy I did a poopy! Daaaaddy!”

The hand picked her up by the cloth of her swimsuit and carried her out of the high chair and over to the changing table. It dropped her down with an audible squish. It went below the table and brought out an incredibly thick, flower printed diaper. Definitely looking to regress her.

“I’m sorry Daddy!” Ariel said “I promise I’ll make it to the potty next time! Please don’t make me wear diapers!”

The hand ignored her and pushed the diaper at her. There was a puff of baby powder, Vanellope assumed the app couldn’t show any private parts, and suddenly Ariel was in the diaper and the hand was holding the droopy pull-up. It dropped the pull-up in a diaper pail next to her. Next it pulled out a short baby dress and dragged it towards Ariel. There was another puff of baby powder and Ariel was changed into the dress.

“Daddy I look like a baby now!” Ariel complained

But the hand was merciless. It gently pushed Ariel onto her back and began massaging her stomach. Grumble! Her bowels rumbled, the rest of the prunes moving through her system.

“Daddy I need potty time before tummy rubs!” Ariel said, doing her best to keep from having an accident but the hand wouldn’t have any of that. Splort! A large lump appeared in her baby diaper. The hand promptly lifted her off of the table and plopped her in a baby bouncer. Squealch!

“Ooh!” Ariel squirmed helplessly as she was forced to smush into her messy diaper “Please, I need changies first!”

It was at this point that Vanellope turned back to the source code. No point watching Ariel get regressed. It would probably take a little while to regress the remaining princesses. She was going to get out, no way she was going to let herself end up like that.

---

“You really like that game.” Paige commented to Darby, watching as he intently tapped on his phone, bouncing baby Ariel up and down in her bouncer.

“Yeah!” Darby nodded “It’s super fun taking care of a baby princess!”

“Don’t you think it’s a little… babyish though?” Paige asked “Like, liking the game.”

“That’s what I thought at first too but the gameplay mechanics are actually super deep!” Darby said “You should try it.”

“Oh, yeah I guess.” Paige tapped on the app to download it. No harm just giving it a quick try. She’d seen several people she knew playing it already today.

“Wait a minute.” Paige stopped and stared at Darby’s pants “Darby, are you, um, diapered?”

“Huh?” Darby pulled back his jeans. Oh that was so cool, he had a diaper on that looked just like the one he had just put on Ariel! When had that happened?

“Yeah, you could say I’m really into the game.” He grinned

Paige shrugged. Wow, this app must be really good. She turned and walked away, opening the app. She wanted a challenge, who was the hardest baby? It looked like Vanellope. She clicked to start a new game.

Behind her, Darby stared at Ariel losing control in her bouncer. She was so cute! He tapped on her tummy to help her along. Blllrtch! He giggled. He could smell that mess from where he was standing.

---

Vanellope finally felt like she was finally getting somewhere. She could see how the code was structured. Very clever security, but with a bit of glitching she was sure she could crack it!

She smelled another dirty diaper wafting up around her. She wondered who it was this time. They’d lost most of the remaining princesses to diapers, only her, Aurora and Snow White were left. Aurora had begun taking care of her poopy friends, changing their diapers and feeding them while they waited for a player to select them, while Snow White was sucking on her thumb and playing with the babies. She was so nervous that she had just mentally regressed. 

Vanellope wiped sweat off her face. Phew, whoever it was was really stinky. Was the baby standing next to her or something? She bent over. Her panties pulled tight. Smush! Her own bottom squished.

“Oh no...” She said, all too familiar with the sensation. Her hands went to her waist and her hands touched plastic. She was naked, clad in just a big, giant baby diaper with candy prints and bib. And her diaper was stained brown and yellow.

“Noooo!” She whined, trying to get to the source code only to find that her arms had become too short and pudgy to reach the screen that just a moment ago had been an inch in front of her “No poopies!”

The source code screen closed and another screen opened in front of her. Paige blinked, staring at Vanellope sitting on the ground in her poopy diaper. Vanellope’s new programming took over.

“Hi Mommy!” She drooled “I made a big poopy!”

Internally Vanellope seethed. She couldn’t sound like that, please she couldn’t sound like that...

She watched Paige put her finger on the screen. The disembodied hand picked her up and plopped her on a nearby changing table. Squish! Her diaper squished underneath her. A clean baby diaper floated towards her. Puff! Vanellope suddenly found herself in a clean diaper. And not just that, inside her diaper she could feel herself powdered and lotioned. Whoever had coded the changes was very good!

“Oh...” Vanellope held her tummy “Mommy you should have waited!”

Blllartch! She farted, pooping just five seconds after her diaper change. Vanellope put her thumb in her mouth and sucked but inside her brain she groaned. She wasn’t the hardest baby in the game to potty train for nothing. Accidents after changes were extremely common for her. Luckily, Paige was already pushing a new diaper at her. Puff! Vanellope sighed. There really was no better feeling than a freshly changed diaper!