[ABDL, Diaper Use, Soiling]
Chaldea. The bastion of Humanity’s defense against the forces that threatened it and its history. And the den of so many terrible antics that it’s a wonder they ever got anything done, considering how many times the base has been on the verge of imploding due to these terrifying events.
Take the case of BB, the AI that had jumped into the arms of her new Master after everything was said and done with that horny nun. Not only had she been part of that scheme, although unwillingly, but she had managed to rope the inhabitants of Chaldea into one scheme after the next, just to satiate her nature as a mischief maker.
And unfortunately for said Master, the adorably young Gudao, she was practically unstoppable. Whether it was because she knew how to string him along with her assets, which he admittedly couldn’t resist, or because she was too intimidating when he managed to make her mad. There was no way for him to turn the tables…
Until she went a little too far. The time she made him make a mess of his undies, and she didn’t even apologize. She just mocked him more, making him seem so much younger than he really was. To the point of nearly forcing him into an infantile garment, just to prove a point. He thankfully managed to escape, due to the more maternal Servants butting in and keeping her off him for a while, but that didn’t make the experience any less horrific.
Gudao had to do something. Otherwise, she’d just keep on doing it. And she wouldn’t stop, unless he came down on her hard and fast. Thus, he made his plans, every single one of his Command Seals disappearing in that moment. Now all he had to do was wait for her to fall into his carefully laid trap.
He hoped she’d be her usual overconfident and mocking self. It’d be really cute to see it twisted into pure shame…
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“Maaaasterrrr!”
Almost as if on cue, the purple-haired digital entity made her grand entrance once the boy woke up, giggling as she crept close to his bed. It didn’t matter that he had blown her off the day before, she had come prepared with plenty of ways to tease him for wetting his undies.
“Good morning, BB!” Gudao smiled. He had to keep up a brave face, at least for now, because otherwise his plan would fall apart before it went anywhere.
BB grinned as she got very close to the boy’s face, peering straight into his eyes. “Looks like big bro’s all sweaty. Did you make another oopsie?” She chimed, blinking for a couple of seconds. “Wait. Big Bro?”
“Mmhm. That’s what I am, aren’t I?” He giggled. She had fallen in already. He knew that she’d try something, and the more she’d try, the more the seal’s power would affect her. “Big Bro’s always been there for you, BB.”
The digital entity scowled a little. That wasn’t right. He was Big Bro, not Big Bro… Wait, why couldn’t she remember that title!? She had used it just moments ago! What had he done?!
“H-Hey! That’s not fair! You can’t just mess with me, Big Bro! That’s my thing! That’s the thingy that BB’s all good at, you’re no good at that or at anything!” BB shouted, a childish side poking its way to the surface. She didn’t get it at all! How could he turn the tables on her so hard? And how’d he know there was a way to do it in the first place!? She thought she had thoroughly reminded Big Bro that she was his cute and adorably dominant little sister!
Gudao giggled a little as he saw the look in her eyes slowly grow brighter. The effects of his seal were doing wonders. Turning down her mental age the more she thought about being a bad girl was really working…
“There there, BB. It’s okay.” The young Master said as he grabbed ahold of the much larger woman, letting her head rest up against his chest as he slowly rubbed his hand through her hair. Kinda like she did whenever she wanted to tease him for being so short and easy to bully.
BB didn’t like it. She really didn’t. No matter how warm it made her feel, or how nice Big Bro’s hand felt, or how comfy his chest was, or how it made her heart make all sorts of big noises, she didn’t like it. Nuh uh! She wanted to pull his pants up and show him that he was a big wetty peepee pants, not a Big Bro! This wasn’t fair!
“No fair, no fair no fair no fair!” The much younger-minded woman cried out as she threw a temper tantrum, letting her fists fly all over the place. “No faaaair! Big Bro’s supposed to be small and weak and all cute! Not nice! Not nice at all!”
The more she whined, the quicker she fell. And at the same time, she proved that the command seals were perhaps a terrible idea, as a quiet *frrrt* left her cheeks, causing her to scream even louder as she realized what happened.
Gudao himself was quick to blush when he realized what happened, but this made his revenge all the more sweet. “Are you about to have an accident, BB? Do you need Big Bro to carry you to the potty?” He asked sweetly, whispering into her ear to try and keep her calm. He was sincere with this. Because if she needed the help, it showed that deep down… She really didn’t mean a lot of the things she did to try and bully him.
“N-nuh! BB’s a big girl! Don’t need the potty! Don’t need it! Dooooon’t!” BB shouted to try and drown out the sound of her tummy throwing a fit, as she shut her eyes as much as she could before the real problem started pushing its way out.
Quite the terrible stink started to blow out between her cheeks, thanks to a little something pushing into her panties. A rather sizable log, the filth that she had been storing within herself for quite some time, landed in the seat of her underwear, staining it a deep brown. And unfortunately for her, it wasn’t the only one. It was just the beginning, as she felt her bowels empty themselves further and further.
Gudao watched it all as he kept his arms tightly wrapped around his ‘little sister’. Oh, she kept on screaming and kept on whining as she filled her panties like another baby who couldn’t get to the potty, but that made her all the more adorable. It also satiated the feeling in his heart. How he should’ve punished her with this so much earlier…
“No fair..! No fair..!” BB cried out as tears rolled down her cheeks. This was the second worst thing that had happened to her. Ever. The first was getting involved with that mean nun mama, and now being held in Big Bro’s arms while she made stinkies? That was even worse! “Don’t wanna make poopy, don’t wanna be stinky..!” She sniffled, wiping her eyes with the backs of her fists. This was the very worst..!
Her Big Bro kept on hugging her, no matter how badly she filled her panties. And it made her so warm, so loved. She hated it, but she loved it at the same time. She’d never admit that to him. She’d rather die than tell him… But it really did feel so good…
“Are you done making stinkies, BB?” Gudao asked, as he slowly planted a kiss on her cute cheek. Looking at her now, after she had cried her heart out thanks to her accident, she looked like a completely different girl. A girl that couldn’t hurt a fly, no matter how hard she tried.
She nodded slowly, her cheeks flushing red. Why was she listening to him? Because he was warm. And because her heart knew that she couldn’t say no to Big Bro. Maybe she really was his little sister. Maybe even his littlest, considering the poopy she made.
“Need changies…” The Big Baby muttered as she put her thumb in her mouth, suckling on it to both keep herself quiet, and to distract her mind from thinking that he was better than he was. She just wanted something to deal with her smellies…
Gudao smiled. That she’d give herself over with this little struggle, after everything she had done in her panties, meant that she was on her road to recovery. If he just raised her right, and made sure that she tasted humiliation like this here and there, then she’d end up a much nicer girl in her future. Even if it’d take quite some time.
“Then let’s get you a change. Then Big Bro’s Big Baby can be the cleanest baby in all of Chaldea.” He giggled, with his ‘little sister’ continuing to blush like the oversized child that she was.
He could just imagine the future… And it looked bright, with the soon-to-be-padded Big Baby at his side. Helping everyone, instead of bullying them...