[Diaper Use, Soiling, Humiliation]

"So, has she learned her lesson?"

Hayase Yuuka was fuming as she spoke to the girl at her side. It was bad enough that she noticed that the funds allotted to Seminar suddenly vanished, prompting her to get C&C to go investigate the likely culprit. But the fact they actually managed to bring the girl back was another headache for her. As far as she was concerned, the culprit was a liability. In many different ways.

"Not compared to the last time she was being punished. You would think that she actually remembered what it would feel like to be humiliated like that."

At her side was Ushio Noa. While Yuuka was burdened by being the treasurer, Noa was tasked with secretary duties. Which meant that she was the one that typically communicated with their Teacher, so that she could approve of everything that was necessary. Not that she actually listened to them most of the time, since she was too busy getting addicted to video games with the Game Development Club...

"How many times has it been at this point?" Yuuka asked, rubbing her forehead slightly. She needed a coffee at this point. But the funds still weren't quite secure enough yet, so they hadn't bought any supplies. Leaving her with a craving and a frustrated mood...

"Ten times. This is the eleventh time she's caused trouble. Perhaps the most amount of trouble since she started acting out." Noa noted, a stern look on her face as she smiled. "I believe we need to start punishing her more harshly. Perhaps even take note of her childish behavior and sense of entitlement, and use that as fuel for the punishment."

Yuuka nodded, even as she felt the slightest shiver run down her back as she saw Noa smile like that. She knew that she could pull off a similar smile whenever their Teacher wasted precious funds on random goodies or gifts for the students that didn't deserve them due to their lacking behavior. But there was something absolutely terrifying about the way Noa smiled, despite how similar their smiles were.

Maybe it was because of Noa's impeccable memory. The fact that she could very easily recall an awful incident, and use it against the culprit to get her way. She had heard she had gotten Wakamo to behave for more than a few days because she got her hands on the masked criminal...

"Would you like to do the honors this time, Yuuka?" Noa spoke up, still smiling as her expression relaxed. There was nothing to fear when she looked like this. Even if she could switch vibes on a dime, Yuuka felt safe when Noa was like this...

Which was good. She needed that security to deal with somebody as frustrating as the girl sitting inside detention. With a sigh leaving her lips, Yuuka slammed open the doors and glared straight at the girl currently bound to a chair within...

That pink-haired idiot that was dressed in that bunny suit. That 'cracker' that had dared take all of the funds for herself, just for the sake of... Whatever it was that she was doing. Yuuka didn't bother checking. No, she was more concerned with the act of stealing those funds itself.

"KUROSAKI KOYUKI. HOW MANY TIMES HAS IT BEEN?"

The pink-haired girl currently tied to her chair immediately felt her heart and her blood freeze as she heard that extra angry voice shouting at her. Her worst fears were realized. She was facing two of her Senpais..! The most terrifying, awful, horrifying members of Seminar..!

"H-H-Hey, Y-Yuuka!" Koyuki cried out as she remained perfectly still in her chair. She had tried to break free about a few hours ago, but she realized she was too weak... But now? She didn't even try to look like she wasn't enjoying herself. She needed to look as presentable as possible, because otherwise Yuuka was going to tear her limb from limb! "I-I-It's been a while, hasn't it?"

Yuuka's face was absolutely smothered by the red shades of anger, especially as she came close enough to practically stare straight into Koyuki's soul. All while the fumes of anger radiated off her too, making it clear that she wasn't very fond of the girl's actions. Especially since she had done this shit far too many times.

Noa approached as well, and Koyuki could feel her soul leaving her body as that girl smiled with her face framed in shadow. If there was one person that Koyuki feared more than Yuuka, considering her tendency to play fast and loose with money, it was Noa. Noa knew everything there was to know about her... All because she had tried to ask her if she could have some help crafting a new identity. Noa didn't think anything of it initially, but after finding out that it was used during her cracking...

"How do you do, 'Little Sister'?" Noa said. Though despite how nice she sounded, it was clear that she was anything but nice. If anything, she was about to burst with rage just as much as Yuuka was. It's just that Yuuka's rage was a lot more openly violent. If Noa started to rage and point all of her rage at Koyuki... The girl wouldn't exist much longer after that...

"I-I don't know what you're talking about, a-ahaha..." Koyuki knew very well that there was no way to get around Noa's memory. Just as she knew that there was no way to get past Yuuka once she found out the funds were embezzled. That was why she had run away in the first place. And yet she was dragged back here.

Right in front of the two girls that were the worst possible match for her. Right in front of the two girls that knew exactly how to break her, and how they wanted to do it. Right in front of... R-Right in front of..!

"The sooner you confess and say you're sorry, the sooner we can start putting you back to work, Koyuki." Yuuka said, actually putting in a bit of restraint as she spoke to her. She was being pragmatic. Knowing that the girl had her uses... And that they had uses for said uses.

Noa nodded and smiled as well. "If you promise you'll never do it again, I might actually treat you like the sister you wanted to be. We'll even go through the trouble of changing your papers. So you'll stay with me. Until you repent."

The mercy they seemed to be giving would've sounded wonderful. If they were offering it to anybody that wasn't named Koyuki. Because despite how much of a naughty girl she had been, despite how many times she had been offered this mercy...

She knew that they were hiding greater punishments behind it. Not that they would actually punish her and spank her and make her do menial labor...

It was the idea of being made to do work, with them checking everything, that sent the biggest fear through her. The biggest... f-fear... fear...!

As the two smiling members of Seminar hovered over the pink-haired bunny, a very brief yet very potent *FRRRRT* left Koyuki's rear. And before long, a strange stench started to waft from her... bottom. Oh. Ohhh...

Koyuki could feel the tears running down the sides of her face as she realized what she had done. The fear that had filled her had forced her to vacate her bowels. As a result, she was now sitting in her own shit. In the messy rope that had been pulled from her rear, resting in the back of her bunny girl leotard. Resting in such a precarious position where she could leak even further if she were to move even a single inch.

"Koyuki..!" Yuuka could feel her anger rising. The girl had shit herself. She was supposed to be better than this! The fact she shit herself, to her at least, seemed like an act of defiance. An act of asserting herself as an overgrown child that did everything she wanted because she simply wanted to. Which frustrated the treasurer beyond all belief.

Noa's smile, on the other hand, grew way more chilling and concerning as she realized what Koyuki had done. "I suppose it's only fitting that a girl that never learns from her mistakes is revealed to be a pants-filling baby." She said with such a calm tone, as she gently patted Yuuka on the back. "Calm down, and go fetch the emergency diapers. The ones that Teacher bought as a gag gift for Problem Solver 68." Of course she'd remember such a gag gift. It was one that brought such a shocked expression to the girls' faces...

"You're right. She does need those. Don't do anything until I come back, I'm not missing out on this!" Yuuka shouted, as she stormed out of the detention room as quickly as she could. She knew that Noa had something wonderful in mind for the stinky bunny, and she was going to watch. So that she knew what to avoid when she got Noa angry.

Koyuki shivered and sobbed while sitting in her own shit. With Noa's expression still bringing her intense fear. "S-Sowwy, N-Noa-nee..!" She cried out, bawling her eyes out as she tried to act like the messy baby that she had turned herself into.

Unfortunately, no amount of apologies would be enough at this point. Not with what Noa had seen her do time and time again. "You'll probably forget the lesson you're meant to learn from this. But don't worry. This time, I know how to make you retain that knowledge." She sounded so frightening. So fear-inducing.

So much so that it wasn't hard to hear Koyuki wet herself too. The faint hissing of pee rushing out onto the seat of her chair, and the piddly droplets splashing into a puddle on the ground...

Noa's disdain only grew as Koyuki sobbed and wet herself, with the memorizing secretary turning around to face the door. By her usual estimations, Yuuka should be back...

"Here! Sorry about the wait, I got them!"

Yuuka rushed in through the door the moment that Noa turned around, with the white-haired girl smiling in turn. "Put the pack on the floor. And then help her onto my lap." She gave a simple request, turning her attention back towards Koyuki as she kept smiling in that deeply unsettling fashion...

"Got it-" Yuuka said, before reeling from the stink and the added pee. "She really needs these. And she needs to LEARN WHEN TO QUIT!" She was still angry, and vented by yelling at the culprit. Who simply sobbed like the big baby that she was. Even as she was being freed from her chair.

Then again, she ended up on Noa's lap a moment later, so it's not like she was truly being freed. Instead, she was made to look straight up at the girl that had such menacing intentions for her. The girl that she had made into 'her sister' according to a couple of the fake identities she had thrown together as a cracker.

"D-Don't... D-Don't hurt me, N-Noa-ne-"

*THWAP*

"A-AHHHH!"

Unfortunately for Koyuki. Not only were her pleas ignored and cut off, but she was definitely hurting from the fact that Noa was spanking her. It wasn't even a small spank, the kind that you would use on bad girls that needed to learn that they had done a bad thing.

No. These were full power spankings. These were all the power that Noa had, packed into one strong swing. She could feel her rump reddening from the sheer intensity of that spank. Like she was about to pop from how hard she was hurting...

And then Noa spanked her again. The *THWAP* sounded echoed out alongside Koyuki's pained sounds, as she wasn't about to escape her fate of being spanked for all of her misdeeds. She needed to be thoroughly, thoroughly punished...

It wasn't enough with the pain either. In fact, Noa seemed to be targeting specific parts of Koyuki's rear. Not just the parts that she knew were the most sensitive and thus vulnerable, but also the parts where most of the messy business had gathered. Ensuring that she became even messier from her spanking...

The *THWAP* sounds just kept on coming. One after another. Each more deliberate than the last. Each more intense than the last. Each making Koyuki cry out more and more, until the poor girl was outright sobbing from how much her poor butt had been hurt. It's not like she could do anything to make it hurt less either...

Because she deserved each and every single spank. No matter how much she thought that it had been the two girls' fault for making her run away and indulge in her gambling needs, that didn't mean that she didn't understand it deep down. She was a lot more insightful than either of the two would give her credit for.

Which made the spanking... Which made the way that all the messy stuff was smeared across her cheeks... Which made every single bit of all of this hurt that much more.

But eventually, the spankings stopped. Noa gently patted Koyuki on the head, while at the same time rubbing one of the spots she had spanked. Rubbing it, and smearing in more of the mess that had coated that part of her butt. Which just made her 'little sister' cry out more. Sobbing like the baby she was, because she had deserved it all.

Yuuka had watched, of course, and trembled a little as she saw Koyuki's butt being rubbed. She had nearly felt the sensation of being spanked so thoroughly by Noa, despite being nothing more than an observer...

"She's not quite done." Noa said, as she motioned for Yuuka to come closer. "Here. You wanted to work out your anger as well, didn't you? I need to prepare something, so you can take over from where I left off." The secretary student said with that same angelic smile, even as she gently spanked Koyuki to remind her that her punishment wasn't over.

Yuuka nodded as she took over, swapping seats with Koyuki. And even narrowing her eyes a little as she felt the girl resting on top of her lap. It's like she could tell that the girl was a lot less comfortable on hers... And it wasn't just because she was still in pain from being spanked that much.

"You're having bad thoughts, aren't you, Koyuki?" The treasurer said, with more of her pent up rage hidden in her words. Rage that made Koyuki tremble as she listened to her...

Koyuki very rapidly shook her head. "N-N-No! I-I pwomise to be good! Pwomise!" She couldn't even keep herself from slurring her words because of how much she had been spanked. She really, really hoped that she wouldn't have to endure more. The tears on her face hadn't even dried out yet, and she was still hurting a lot. She didn't want her poor butt to get spanked more than it had been, because she was sure that she wasn't going to be able to sit down if it continued!

"You ALWAYS say that! And you NEVER keep your promise!"

And yet she had said exactly the one thing she shouldn't have. Which resulted in Yuuka starting up the spanks again. And despite the fact that she was a lot less proficient in picking out the spots that could deliver the most punishment, she made up for that with sheer intensity of spanks.

*THWAP* sounds echoed through the detention room for minutes upon end. She just kept on spanking, and the sobbing baby got what she deserved. It definitely seemed like it would never end, with the kind of intensity and ferocity that the spanking girl was able to put out...

But before long, the spanking came to an end. Just as Noa returned, even. Leaving Yuuka to pant and gasp from how much effort she had put into punishing Koyuki, which meant it was time for the white-haired girl to take over again.

"Goodness." Noa said as she helped Koyuki onto the floor. All while amusedly watching the red hues pierce through the layer of stink that covered up the inner side of Koyuki's bunny suit. "She really did a number on you. But don't you worry. You'll get your change."

Koyuki couldn't respond. She was still crying. Still silently sobbing after everything she had been forced through. Still simply laying there like a good girl who knew not to say anything back to the ones that were there to care for her. Because she had been far too bad for them to go easy on her.

She was stripped of the extra stinky bunny suit, and Noa helped her slowly recover from her stinging butt. A few wet wipes were used to clean away all the icky, stinky, extra squishy poopy that had left her rear. Leaving her sensitive butt as nice and wet as it could be, while leaving her ready for a change as well.

Of course, she didn't want to be diapered. But she didn't have a choice in the matter. She simply sucked it up and closed her eyes as her legs were lifted into the air, and a diaper slid right underneath her butt. Letting Noa quickly weave it in between her legs, and then snap the wings shut as she lowered her legs...

On the front of the diaper, matching the shocked expression she had earlier, was a cute print of Aru. No wonder it had been a joke gift for Problem Solver 68. But right now, having her pained butt wrapped around by a cushy pamper... Actually felt kind of nice...

But one good look at Noa made it clear to Koyuki that her punishment was far from over. Especially since Noa had brought her old uniform...

She was going to be stuck with Seminar from now on. As their Baby. And knowing Noa and Yuuka's vindictive nature...

Koyuki couldn't help but worry and sob a little, as she wet her diaper for the very first time...