[Fat, Soiling, Diapers, Diaper Use, Futanari]

"She better appreciate this. She's done really well lately, so..."

Miyu Edelfelt was currently walking through the halls of the Einzbern family manor, dressed in a maid outfit. Due to her agreement with Luvia, this was her normal attire. And as it turns out, it was one that her fellow Magical Girl really liked. So since she had done such a good job with the Class Cards, she thought it'd be fitting to reward her. Though at the same time...

Her friend, Illya von Einzbern, was very near and dear to her. And that was why she wanted to reward her. But it was also why she was cautious to do so normally. Illya was a rather impulsive girl after all. Which was evident with how the young girl had managed to grow so plump in such a short time. Certainly wasn't helped by Miyu taking her out to eat more often, because she had to eat a heavy dinner after work and her duties as a Magical Girl. So while she definitely did things that could maintain and regulate her body weight, Illya...

Well, Illya had gotten fat. And that was why Miyu was nervous. If she rewarded her too much, she might get fatter due to the nature of those rewards. But if she didn't reward her, then... Oh, it was just a massive hassle. Something that Miyu really didn't want to deal with. But Illya was such a good friend. So it was just something she had to deal with. And right now...

Miyu just had to hope that the girl was happy with seeing her in this outfit. And if she wasn't... Then she'd have to put her on a diet, so she could treat those big meals as a reward, rather than an incidental thing.

"Illy-"

As Miyu opened the door, ready to show herself off, she noticed Illya looking at herself in the mirror and looking rather fussy. But that wasn't really what she noticed. No, Miyu noticed what was currently hanging at Illya's waist...

"I can't believe Mom wants me to wear these... I'm not so fat that I can't make it to the potty..."

Illyasviel von Einzbern, commonly known as Illya to her friends and family, had definitely seen better days. While she was still able to fight against the Class Cards and threats like them, she had really been getting fatter. And she kinda knew why. It was because Miyu kept on eating such big meals, and she just couldn't say no to a food date with Miyu. But since Illya's duties weren't as intense as Miyu's, it all just kept on packing on.

Which was why she was currently unable to really wear her usual uniform. Her gut was hanging out over her skirt, and the skirt itself was clinging to her fat ass instead of her waist. She wasn't like, fat-fat, but she definitely could offer up her belly as a pillow for Miyu if she so wanted. It was humiliating to look at herself in the mirror for that reason...

And her Mom definitely noticed. Not that she could ever hide it from her. Which was why a cutesy pullup was currently clinging to her waist. She was lucky that they had pullups in her size, because if she got any bigger... She might actually need diapers. These were bad enough, especially given the Magical Girl print on the rear. But hope...fully...

Illya's eyes widened as she noticed Miyu in the reflection of her mirror. "M-M-M-MIYU!?" She screamed in shock, whipping around with her face immediately turning bright red. Her shame filled her heart in an instant...

Miyu was blushing just as much as Illya was, since she never expected to see her friend in a pullup. "I-Illya, what are you wearing!? Is that a dia-"

"Just a pullup!" Illya instinctively shot back. It was bad enough that she was wearing this thing, she wasn't going to have it confused for something way worse. "Just! A! Pullup!" She cried out. All while her cheeks flushed even brighter red. She... She felt something. And she didn't want to think about what she just felt. Because... If it really was that, then...

Unfortunately, Miyu did notice as she pinched her nostrils shut. "T-That smell... I-Illya, you pooped..?" She muttered in shock. It was really so surprising to see her fall so far in a mere instant. She knew that Illya's Mom had things in mind to try and help her lose weight, but to see her try this as a method of keeping her clean... And for Illya to immediately use it...

...Miyu had to make sure she didn't let Illya know that she found the shocking and stinky display arousing. Because... Well, her panties were getting a bit wet from the cum leaking from her. It was bad enough that becoming a Magical Girl made her cock grow, but to think that she would be aroused from seeing her friend like this...

"N-No. N-No I... I didn't..." Illya tried to protest, but she knew that it was the truth. And no matter how much she'd try to hide it, Miyu had seen her do it too. She had seen her fill the seat of her pullup. "Miyu, c-can't you just... J-Just go..?" She muttered as her reddened face had its hues deepen. She didn't like any of this. And she didn't want to think about it or talk about it any further.

As much as Miyu wanted to give her friend the chance to recover, it would've made this getup a waste. "...No. I'm not leaving. Not while you're stinky like this." She said, remaining firm in the face of such a humiliating display. If she were to leave her here too, she might interpret it as something worse. "Get on your bed, Illya. I'm going to help you with this, you big poopy pants."

Being called poopy pants was humiliating. As was being called 'big' considering her current weight. Being called both at the same time? It was shameful enough to the point where the front of her pullup ended up getting a bit stained. And as such, she really couldn't say anything against her. All she could do was go over and lay down on the bed... With her rear currently facing the ceiling and her legs hanging off the edge of the bed so she didn't dirty it...

The first thing Miyu did was open the window so the air inside Illya's bedroom didn't end up as stinky as her butt. Then she quickly scoured the room to look for the necessary supplies. And while she found a pack of pullups that matched the one that Illya had dirtied, she also found a pack of diapers that had yet to be opened, one with another Magical Girl design that almost looked like a bootleg version of Illya's Magical Girl self printed on the front.

"Illya, have you messed yourself like this before?" Truth be told, she didn't know how long Illya had been stuck in pullups for. But she wanted to make sure if there was a repeating pattern. If there was, then she definitely needed diapers. Which was why she had already grabbed one, just in case.

Illya paused. And she nervously shook on the bed. "D-Does that really matter? D-Don't you just need to wipe my butt and toss the pullup out?" She asked, trying to obviously dodge the question. She really, really didn't want to think about this longer than she had to. It was really, really humiliating...

"Illya." Miyu's voice turned stern. Almost like she was living up to the role of a maid. She was dressed like one after all, better play the part. "Please. I don't want you to make your Mom angry. Because nothing I could do would even come close to being as bad as what she would do to you once she found out."

Miyu's words were weighed down by the truth. Even if Illya didn't want to think about it or acknowledge it. "...I... I've wet the bed a few times, and I didn't make it to the toilet one time after we fought together, and Mom found the stain in my panties even after I tried to clean it..."

It was settled then. She was developing incontinence. Whether it was due to her weight or due to something else, she definitely couldn't be trusted in pullups. Especially if she pooped herself from nothing more than being startled.

"It's diapers from now on. Alright, Illya? At least until we figure out if you can get this fixed or not." Miyu said, trying to smile. So that Illya might not think as much of this.

Illya looked to her once, and... Well, she couldn't say no to that smile. Even if it was tied to something as humiliating as wearing a diaper. "F-Fine. But just... Just wipe me clean first, then we'll think about the diapers after that..." She muttered. She really didn't want to wear one of these. Really, really didn't.

With Illya agreeing to her proposal, Miyu went to work. Stripping her of the dirty pullup and tossing it in the nearby trash bin, making a mental note to carry out the bin later. And then faced with two things she had to deal with. The first being the sticky stinky that was clinging to the girl's rear, and the other...

The other was Illya's baby dick. Because Illya hadn't been born with a cock, she only managed to grow one thanks to her transformation. But it was so painfully small. At least when compared to the tent that was currently pitched under Miyu's skirt. At the same time, it was so adorable... And incredibly sticky, given the cum that was currently covering it. She had cum from the humiliation, it seemed. Which meant that Miyu needed to clean that as well...

Honestly, seeing her like this... Seeing her when she was this vulnerable... It made her own cock drool a little. It was a good thing that her panties were able to soak up the cum that tried to sneak out of her, because otherwise Illya might've noticed that she got off to the sight of her...

Illya let out yelps as she felt the wet wipes rub up against her butt, and especially as she felt fresher wipes get rid of all the cum that had gathered around her cock. She usually tried to ignore that tiny thing, but it was beyond sensitive. And as a result, it didn't take much for her to end up cumming straight into the wipe...

Thankfully, Miyu could quickly wipe that clean. And before long, she had managed to clean her friend's rear and her crotch. Leaving both spotless, even if the tiniest trail of cum was trying to drool its way out from Illya's baby dick. If she didn't do anything about it, it was probably just going to keep leaking. And make a complete mess of the entire place in the process. Which was probably another reason why Illya's Mom put her in pullups and considered diapers an appropriate measure.

With Illya wiped clean, Miyu pushed her onto the bed slightly so she could roll her onto her back and then slide the diaper under her rear. With the seat of the diaper snugly situated underneath her friend's rear, it was easy to weave the midsection through those tenderly thick thighs that the plump girl was saddled with, and then snap the tapes shut once everything was aligned. After that, she just had to pat her hand against the diaper to make sure that everything really was shut properly...

Which meant that her hand pushed in against Illya's crotch, and naturally started to arouse her again. Within seconds, that nice and clean crotch turned sticky. Not to the point where she needed another change, but it was impossible to mistake her sudden shifts and gasps for anything but a quick orgasm.

"I don't know if you getting fat, you needing diapers, or you being such a quick shot is more humiliating..." Miyu muttered before just shaking her head and curtsying like a proper maid once she took a step back. "How'd I do?" She asked, smiling as she tried to ease the tension in the air.

Illya looked down at the diaper she was wearing. That thick garment that was cradling her. The garment that made sure that she wasn't going to be going anywhere anytime soon. She was going to be waddling all over the place, and that was if she could actually get up. Just how did Mom think she could walk around in something so thick? More importantly, why did it feel good..? Why did it feel so nice to have that soft padding rub up against her crotch, to the point where she already came..?

"...Y-You did a great job, Miyu!" Illya shook her head as she tried to focus on what mattered, blush still filling her cheeks. As bad as it was to wear something like this, Miyu had done a great job. And... Well, the maid outfit and the curtsy really helped her vibe, so it wasn't all bad. "M-Maybe if it ever gets this bad again, you could-"

"Not a chance." Miyu immediately shut her down. Illya was a great friend, but despite the outfit... Miyu wasn't a maid. And if she did change her more, Illya would probably figure out that she was enjoying it too much. She couldn't allow that to happen. Not when she was still this big... Not when she could grow bigger, as Illya would probably think of trading a good meal for a change...

Just as Illya started to pout as MIyu denied her the chance to receive the kind of love and care that she needed, the door leading into Illya's room opened again. Or rather, it was slammed open. Despite Miyu having locked it so only Illya and herself could enter... Which meant...

"Illya! I need a fresh diaper!"

The one that cried out had a voice very similar to Illya, yet Miyu was accustomed to it at this point so she could tell the difference. She could also tell that the owner of said voice was even stinkier than Illya, as she could smell the stink even though she was facing away from her. But she decided to look over her shoulder to assess the damage, despite knowing that things could only get worse from here.

Standing right outside the room with a diaper sagging far below her knees and wafting around its horrid smells, was Kuro. Or Chloe, as she decided to go by after she had become part of this world's family. She was another version of Ilya, and that was the simplest way of explaining it. Regardless, it seemed as if she was just as incontinent as Illya... And just as fat too, considering she was wearing her usual casual outfit, just with a button obviously having popped on her pants. Whether that was due to how much mush she had packed into her diaper, or just simply because of her heavier frame was anybody's guess.

Chloe took a moment to take in what was happening here. And she narrowed her eyes. "You'd give her a change, huh, Miyu?" She said, as she stomped over to her fellow Magical Girl. "She's not the one who's been having troubles properly maintaining her mana and needing diapers because of it, so you'd better give me one too!"

"You're filling your diaper because you just keep eating, Chloe!" Illya cried out as she tried to get up from her bed, only to immediately lose balance and end up squarely on her padded posterior, the sound of the crinkling garment filling the air. Which just served to embarrass her further, especially as a bit of cum poured down.

Miyu tried to say something, not wanting either of the two girls to start fighting. Not like this. Because that would mean Illya would end up drawing attention to herself, and the last thing she needed was attention. Especially when she was in a fresh diaper that had yet to be properly messed.

But Chloe noticed something. Something that Illya had neglected due to her own panic. "Miiiyuu..." The tanned girl said as she stepped closer to the maid with the obvious tent pushing up her skirt. "What are you doing there..? Is that your cock I see..?" She mused aloud, grinning from ear to ear. Miyu really got turned on by them in diapers, huh?

Now it was Miyu's turn to flush bright red, especially as Illya also focused her eyes on her. "I-I don't know what you're talking about, Chloe. You must be seeing things." She tried to play it off. "I-It's just some lingering morning wood. Y-You know how it is!"

"I do. But I usually get rid of it." The chocolate-hued girl said as she took another step closer. "Illya, what do you think this erection's for? You know she doesn't get hard during fights like I do, so what could it be for?"

Illya let the thought drift through her mind for a moment as she put the pieces together, only for her eyes to light up seconds later. "Miyu, did you get turned on by my poopy butt..!?" She cried out in shock. It was bad enough that she was caught filling her pullup. But to learn that Miyu was turned on by the sight was another thing entirely. She couldn't believe it. Her friend would get hard because of her condition..!?

"N-N-" Miyu tried to stutter, only to suddenly gasp out and moan as she felt an extra heavy mess push up against her crotch. Quickly flipping her skirt in the process, and barely revealing the meat tenting her panties despite how easily it was smothered by the full diaper...

Chloe grinned as she could feel the cock hardening as she pushed up against it. "She's definitely into it. How's it feel, Illya? How's it feel to watch her get hard because you made a mess?" She asked, all while making sure to push a little harder into that cock and force another louder moan from Miyu's lips in the process. "Maybe if you hurry up and fill your diaper again, you can make her cum too.”

"It's not fair that you're hogging all the fun!" Illya cried out as she glared at Chloe, who smugly grinned back at her. It was bad enough that she knew that Miyu got off to this. It was way worse knowing that she didn't admit it. Especially when it was clear that she was really aroused, as she could see the cock throbbing against that soft padding.

Miyu tried to protest. But she didn't get very far. Especially not as Illya started to push once again. But not just pushing things out. No, she also got close enough to the point where her diaper was brushing up against Chloe's own diaper, trapping Miyu's cock between two crinkly garments.

It barely took any time for her to cum. She could feel both of them pressing down against her. It was intense. It was so intense that she felt like she might just blow again almost immediately after cumming. But she could smell it. She could smell how foul the scents that flowed out of Illya were. She was about to go poopy. And if she thought that she was overwhelmed when she was stuck between a clean and a dirty diaper, then...

The sound of a brassy fart echoed out for a moment, right before Illya's seat started to expand. Her diaper was making sure to spread out as far as it could as the torrent of Magical Girl Shit poured straight into that thick padding. She could feel her legs spreading apart and making it harder to stand. But that didn't matter. No, what mattered to Illya was the reason why she had started to fill her diaper.

And the reason was also why she and Chloe were currently pressing their diapers harder and harder against each other. Because even as Illya's diaper expanded, the moans that had begun just a few moments later didn't stop. No matter how big the diapers were, no matter how stinky. It all felt really good to have them pressed up against her cock like this.

"T-Too... Too much..." Miyu gasped as she felt her cock throbbing far faster than it ever had before. She had only just awakened this fetish, but now she was on the receiving end. If they kept on pressing against her like this, then she was just going to need it even more. She might just wear a diaper alongside them, just to feel the softness pressing against her cock like... like...!

A powerful cry echoed from her lips as Miyu's body was assaulted by the intensity of her first proper diaper-enabled orgasm, her cum splattering straight onto both of those poopy pampers. All while her body grew a little limp. She was still standing, thanks to the way the two were pincering her cock. All it would take for her to topple over was for them to let go of her. And yet they didn't let go.

"That's it?" Chloe asked, as she grinned a little more. "Come on. You can thrust to your heart's content, Miyu. But once we're done, you're going to have to wear one with us. And I expect you to fill it just as much, if you're going to be such a poopy pamper lover." She was going to make sure that Miyu couldn't escape her new fetish. All while looking to Illya. "Come on, Illya! You want to see her keep cumming because of our diapers, don't you?"

"I want a change, but if she's going to wear diapers, then she'll stick around us more!" Illya cried out, as the plump girl thrust her hips back and forth. Not just so her baby dick could properly rub up against her padding, but also so the diaper was grinding against Miyu's cock. "So come on! Cum again, Miyu!" Her embarrassment had completely faded at this point. Replaced with the rush that came with being dominant.

Miyu moaned more and more as the two poopy pamper packers really squeezed their diapers against her cock. And thanks to how they were rubbing up against her, they were making her thrust. Back and forth. Against all that stinky stuff packed in there...

It was overwhelming on every front. So naturally, it didn't take long for Miyu to cum. Again... And again... and again... She came so much in such a short time. And yet the amount that fired out remained the same, glazing both of those stinky babies' butts in much of her extra sticky seed...

Before Miyu was forced to collapse, the two girls accidently spacing their diapers apart just enough for Miyu's thoroughly tenderized cock to stop trembling and allow her to pass out when she hit the ground. All while smiling in such a blissed-out way. Like she had been forced to experience heaven...

"Heh. And she calls me a quickshot." Chloe said, before turning to Illya and grinning as she quickly wrapped her arms around her 'other self'. "So. How about we make that baby dick of yours cum a little more, until our pamper-loving maid decides to wake up?" She was more than willing to have more fun with Illya. Especially since she hadn't yet reached her climax.

Illya squirmed as she felt her cock squirt out more of her extra dribbly cum, before wrapping her arms around Chloe in return and digging her hands into that extra dirty diaper. "Maybe you're the one who'll be cumming lots! How about that, whoever cums the least gets to put her back in diapers and gets the first change?!"

"You're on!" Chloe laughed, as their little erotic match began. Pressing up against each other, cocks pinned against their crinkly garments as they both let their arousal climb uncontrollably...

All while Miyu laid in a puddle made from her own cum, unaware of how much further she could fall once she woke up...