[Weight Gain, ABDL, Diaper Use, Soiling, Hypnosis, Mental Regression]

Being an Idol was a difficult gig. Sure, you got all of the singing and dancing you had to do on stage, but you also had to do a ton of back-stage deals to make sure you stayed relevant. Whether that was advertising deals, having to listen to unsavory types' orders or other such degrading things, it really was a difficult business.

So, when young and rising idol Kujikawa Rise managed to snag a deal with an equally rising corporation that wanted her to advertise a multitude of her products for them, who was she to say no? Especially since they seemed to have capital to throw around in spades, otherwise they wouldn't have booked an entire week for her all to themselves.

"I mean, I get that big business thinks that it can do whatever it wants, but..." Rise muttered a little as she crossed one leg over the other while staring across the table, staring straight ahead at the young man that had managed to get ahold of her for his own devices. "I never expected one of those bigwigs to be a little kid. I mean, aren't you supposed to be in grade school? Maybe kindergarten? How come you're actually running one of these corporations?"

The white-haired youth chuckled in response. "You've seen the type of girls you compete against, and you're complaining that I'm the one that's too young to do things? You're very harsh, Miss Kujikawa." His red eyes pierced straight into her own as he leaned back in his chair. "Still, I can take a little bit of banter. I didn't pay your agent a veritable fortune to just have you over for a quick chat where you could express your surprise at my standing, after all."

Rise raised her eyebrow briefly. "Then what is it? You wrote something about a product you wanted me to advertise, and... Well, my agent says that I have to take any deal, no matter how embarrass..." She started trailing off as she realized the potential problem that might arise. "...You're going to make me do something humiliating, aren't you?"

"You catch on quick!" The albino boy, Atlas Grimwald, replied as he pulled out the product that he wanted her to advertise. A big bag of adult-sized diapers, already wearing the idol's face on the side of it. "Diapers. Super absorbent, totally leakproof, and as comfortable as a mother's bosom. Trust me, we deal in the highest quality stuff, and we wanted the highest quality idol on the market to advertise them." He launched into a little advertising spiel, only to laugh a moment later. "Oh, and don't worry, they're not on the market yet, these are just a production sample so you can get a feel for everything."

The idol narrowed her eyes as he spoke, causing another few worries to arise in the back of her head. Everything the young man did raised at least a dozen red flags, and yet... Well, she'd be disappointing her agent if she didn't at least try them on and figure out if she liked them enough to go through the humiliation. What was going to be so bad? "At least they're not actually in stores right now, I'd hate if you ruined my reputation before I even had a chance to do so myself." The brunette replied, chuckling a little herself in an attempt to make the situation feel a little less tense.

Atlas smirked as he ripped a hole in the packet, pulling out one of the diapers, which seemed to be just as big as his legs were long. "Well, you need any help getting this on, or do you prefer to deal with it yourself? Trust me, I've got the skills to change a girl your age." He seemed far too confident, and it just kept getting under the brunette's skin the more he spoke. But she had to stay composed... despite that ever-present and ever-worryingly smile on his face.

Rise gulped a little as she reached for the padding, shaking her head in response. "Oh, don't worry. I won't need a kid's help. Even if I'm going to look like a kid in a little bit, you know, I want to keep just a little bit of pride. A teensy bit." She tried to assure him that she could do it herself, but something felt off as she held the padding within her hands. Something... felt as if it was missing. Like, the more she looked at the white piece of underwear meant for babies that never really grew up, the more it felt like she couldn't tell heads from tails? Like, how was she actually going to get it on?

The little boy smiled a little wickedly as he climbed off his seat, walking around his desk as he planted his firm hand on the older-looking girl's bottom in response to her confusion. "You're looking awfully perplexed, Kuj... No, Rise-chan. Don't you want a little help from somebody that's experienced in changing babies?" His voice was a lot less smug and secure of himself at this point, as it sounded more like he wanted to help her get used to her new role in... wait, new role?... Yeah, that sounded about right...

She paused and squirmed back and forth for a little bit, before nodding in defeat. "...Okay..." She replied in a shy tone before handing the diaper back to the youth. She didn't even need to be told that she needed to remove her clothes, that was a natural thought that crossed her mind after submitting to his demand. After all, babies needed to be naked when they were getting changed. That's how it went, right? They also needed to lie down on the floor like good little girls to expose their bodies to their daddies, so they could get a good view of their sweet little angel...

Atlas continued to smile, pleased with the effects that the diaper had on the older girl. He, of course, hadn't mentioned that the fashion department had imparted a few special effects on the fabric. A simple touch from a feminine being would sap their age bit by bit and link them to the nearest person, designating that person as their caretaker or 'parent'. In this case, the shota now served as her Daddy, whether she consciously acknowledged it or not.

Rise didn't move an inch as he slowly slid the back of the padding under her naked bottom. She only started to move a tiny bit as he moved the middle of the thick diaper through her thighs, her breath growing tense as she felt her arousal spiking, another side effect of the massive diaper that she'd be wearing for quite some time. Once the padding had been snugly weaved through her thighs, it was just a matter of snapping on the tapes, and presto. By the time the little baby girl sat up on her snugly soft and secure bottom, there was at least a foot between her crotch and the floor, that's how fat that diaper was...

"It's... a little big, isn't it..?" The slowly regressing idol asked aloud as she looked at the red-eyed boy for approval, biting her lower lip a little as she pouted. She wasn't sure of herself, a feeling that she was most unfamiliar with. She always had confidence, and yet there was not a single speck of it to be found.

He merely chuckled as he ran his hand through her hair in response, continuing to smile supportively as he started to push at the front of the padding that kept the idol's legs spread far apart. "It's as big as it needs to be. It's for good girls like you, after all. And good girls are not only big, but they make big messes the size of their bellies."

That made Rise tilt her head a little in confusion. She wasn't fat, and she wasn't exactly big in that sense either. But then, something started to happen. A little rumble started to echo throughout her belly. Then a bigger one. Then a loud groan as she felt hunger panging through her body, a sliver of saliva running down her chin as she started losing control of her newfound gluttony. "... H-Hungry..."

Atlas grinned as he reached over to the desk, before pulling out an oversized baby bottle, having the same width as his thigh. "Here you go, little angel. This is your food. Drink up and make Daddy nice and proud, will you?" His happy chiming felt so off, and yet she really couldn't say no to what he was offering. He was her Daddy, and she was his baby girl. Baby girls listened to their Daddies.

So she did as he asked. She grabbed ahold of the big bottle meant for babies her size, and she made sure that she had a proper grip on it, a task that seemed a little harder than she would've expected. Once her hands were firmly wrapped around the plastic, she latched her lips onto the rubber nipple and started to suckle. Suckle, suckle, suckle. Her eyes dimmed as she just drank and drank, trying to satiate the feeling of hunger in her tumtum.

It actually worked surprisingly well! The more of that sweet milk hit her stomach, the less it started to complain. It even tasted super good, like her mother's milk from way back when. She didn't know why she could remember it, but she knew that she loved this milk just as much. So she just kept on drinking. Suckling, slurping, swallowing like the greedy infant that she was.

Of course, she didn't at all realize that the milk was just as laced with bad stuff as her diaper was. Produced by the corporation's Biotech division, it was designed to complement the diapers. To ensure that the drinker's belly would properly fit the diaper, which felt a teensy bit loose around her waist in comparison to what it could've been. Indeed, as she continued to slurp down more and more of the white wonderful substance, her waistline expanded outward, until the diaper's waistband properly clung to her waist in return. And then some, as her belly quickly started to leak over the top of the band.

It wasn't just her belly that was affected. Her arms had grown a little flabby, her legs widened a bit as they filled out the leg holes, and her breasts swelled at least a cup or three while she continued to drink. She was like an overgrown baby with how the extra fat was divided around on her body... but that's what Daddy said that she was, didn't he?

Speaking of what Daddy said, Rise suddenly felt her belly starting to hurt again. She stopped drinking, huffing about the issue as she looked to the youth she looked up to like a father figure. His smile said it all, as he leaned forward to whisper a single word into her awaiting ears.

"Push."

Of course! That's what she had to do! She was wearing a diaper, she was having problems with her tummy, and she felt so full even further below. Why shouldn't she just push and try to clear up that jam, so she could continue drinking from her bottle like a good girl?

So she did. Push. Push and push until the pressure relieved from her bottom. Until...!

*BLLLLRRRRRTTTT-*

She skipped straight through the part where she released the gas from her bowels, as a full log of poopy poured straight into her pampers. Relief colored her expression as she started to drool like the baby that she was, giggling a little stupidly as the back of her diaper grew and grew, the serpentine snake that was her shit continuing to pour out of her hole with no end in sight. For good reason, given her dome of a belly.

It just kept on pushing, breaking apart after a while before a new serpent managed to sneak out of the widened hole to join its brother of a mess inside of the overprotective padding. Despite how many inches of protection that there were, it still didn't stop the mess from making the back of the diaper sag downward with the weight of it all... And Rise didn't care. She was too being happy over getting rid of the pressure, to the point where she was actually starting to prod at the front of her diaper... which was growing a golden yellow as her bladder started to release its contents just like her bowels were. And she just giggled still, not caring a bit!

All the while, Atlas continued to pet his little fat baby of a girl. Oh, he was quite satisfied with all of this. Not only did he manage to get ahold of a brand new baby for his own entertainment, but he also managed to test out his diapers and his milk. And with Rise under his control, he had the perfect way to advertise them both.

Even if the world would be appalled at her current state.

---

Describing the populace as appalled was right. All over Japan, a demo video was shown of the newly fattened idol dancing like a fatty on stage, trying her best to use her new size to pull off the same moves as before, but to no avail, as she kept tripping and showing off her diapers with her face adorning the bottom of it.

All of her friends were unlucky enough to watch her as well, but they weren't as... repulsed by the sight. No, if anything, the sight of their friend in diapers made them slowly drool themselves. As good girls should be, given the specific programming interweaved into the footage. All girls that were prime baby material would react to the subliminal messaging in her newest performance...

And thus, the other girls in the former Investigation Team ended up giggling like the little girls they were at heart, while their panties grew equally wet and warm. Each of them would soon receive a knock on the door, with a worker from Atlas Corp ready to deliver them to the boy himself. After all, they weren't girls with freedoms anymore. They were babies. Babies that wet their panties.

Babies that needed their Daddy.