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Smirking as she let a small golden coin on a string unfurl from her palm, Chloe von Einzbern couldn’t keep the smugness off her face as her twin sister fell hook, line, and soon-to-be stinker for her plan. Namely, the dark-skinned loli planned to make her so-called ‘big’ sister into the little sister on their shared birthday via hypnosis, especially since she knew Illya’s usual thought process of following the ways of magical girls. One of the most infamous magical girl tropes was falling prey to an enemy’s hypnosis, and Chloe was more than happy to play the villainess if it meant securing her position as the older sister, even if only for a day.
As Chloe adjusted her rear on the seat next to the desk, she cleared her voice to cover any sounds while Illya sat on the side of her bed. “Alright, just watch closely and don’t take your eyes off the coin. Trust me, I’ve been practicing this!” Well, that was only partially true since she had, indeed, done the hypnosis on a guinea pig, but Chloe couldn’t tell if the hypnosis actually worked on Leys or not. There was a reason that two diapers were missing from the pack of diapers she prepared for her sister, especially since she barely managed to get one around Leys’ huge ass. The maid’s panties had to help support the tapes after the initial mess, and it gave Chloe a good chance to practice cleaning someone’s dirty butt before Illya and Sella got back from the store.
Luckily for Chloe, the hypnosis seemed to wear off just in time, although Illya’s response snapped her attention back to the moment. “I know how hypnosis works, duh. We’ve watched enough anime together, although maybe you’ll just hypnotize yourself~ Can you imagine yourself falling asleep and getting ordered around by your big sis?” For a moment, Chloe’s smirk turned to gritting her teeth as that worry had come to mind, but she didn’t want to hesitate. Illya had to fall for this hypnosis. It just made sense for magical girls! Getting hypnotized was a classic Saturday morning trap for her to fall into, and Chloe was sure to abuse it as much as she could.
At least, the brown-skinned loli hoped to do so, although the door to Illya’s bedroom opened as a scowl came across Chloe’s face. “And what might you be doing here?” Of all the people to interrupt her, it just had to be Miyu… The coin in Chloe’s hand slowly swung to a stop while Miyu stared blankly at it, and she only continued once it finally stopped. “You know, there are no proven results for hypnosis. It’s truly nothing more than a parlor trick that individuals fool themselves into falling for.” Miyu’s disdain for the magic was apparent, even if the three of them proved the existence of a magic beyond what normal people could ever believe.
After all, magical girls chasing after class cards granting the powers of heroes, anti-heroes, and villains throughout history and mythos seemed more ridiculous than someone falling for hypnosis, but here they were. All Chloe could do in the meantime was scoff a little before she sighed. “Fine, I’m just trying to mess around before Leys and Sella get back. If it doesn’t work, it doesn’t work. But hey, what if it does?” Her eyebrow raised with the corner of her mouth toward Miyu, all while Illya raised her hand to defuse the situation.
That was short-lived, since the raven-haired girl cut her best friend off before Illya could even voice her concern. “It won’t. Go ahead, if you will, but it will not work.” Such a matter-of-fact statement, and Chloe desperately wished she could wipe that neutral look off of Miyu’s face so badly. The dark-haired magical girl even went so far as to cross her arms, waiting almost expectantly for Chloe to fail, putting even more pressure on the dark-skinned loli.
Part of Chloe wished she had attempted the hypnosis on Sella instead of Leys to figure out if it worked correctly, but there was no better time than the present. Taking a deep breath, she steeled herself in case of disaster, although Chloe hoped that Illya would be the one having a disaster in her panties soon enough. “Let’s try this once more. Keep your eyes on the coin, and on the coin alone.” With that, Chloe began to swing the coin back and forth, watching Illya’s eyes closely follow it. Out of the corner of her eye, she kept an eye on Miyu since the dark-haired girl kept her eyes on the coin as well.
“Now, focus on my voice, and follow my commands.” The dark-skinned girl did her best to hide her unease at seeing Illya readjust herself upon hearing that, although it looked like Miyu was the one getting more comfortable as the dark-haired loli’s arms dropped to her side. As much as Chloe wanted to prove Miyu wrong, she had to be the one focusing on what was important, and that was Illya in front of her as she gulped down the lump in her throat. “You’re feeling very warm inside, and your bladder is feeling very full, as if you really need to use the bathroom, but you can’t move away from your seat.”
The confused look on Illya’s face told Chloe all she needed to know about how well this was going, but even as Illya opened her mouth to interject, Chloe continued. “However, you don’t remember how to use the bathroom anymore, since the only bathroom is now the one around your- hiiisssssssss” Chloe’s eyes went as wide as Illya’s as they stared at each other in shock at such a sound rising in the room, although both of their attentions quickly darted to Illya’s crotch. The light-haired girl spread her porcelain legs, although the crotch of her shorts remained completely dry. Right after, Chloe dropped the coin as her hands darted to her crotch, but her jean shorts were still clean and dry as well. If neither her nor Illya had wet themselves, then that could only mean…
Chloe and Illya both gave each other a worried look and took a breath before looking toward Miyu, only to see the raven-haired girl in quite an unnatural state. Miyu’s eyes were glazed over, her shoulders slumped slightly forward, and, most importantly, her pants were drenched with urine as a puddle continued to grow on the carpet below her. “Chloe, d-do something!”
“Do what? I… I didn’t think Miyu would be the one falling for this!”
“Then what? Is this what you were trying to do to me?!”
“M-maybe a little! But to be fair, it was just because you always try to be the big sister!” By now, both girls stood off their respective seats and argued in each other’s faces. “I didn’t mean to make Miyu into the baby sister.”
“Baby… sister…” The dark-haired girl’s voice caught their attention once more, especially as Miyu slipped her thumb into her mouth.
“Eh? Miyu, what are you doing?” Illya started to take a step closer toward Miyu as the latter moved to a partial squat, but Chloe put an arm in front of her sister. It didn’t take long for Illya’s confusion to be quelled, especially as Miyu barely grunted and a wet, mushy fart bellowed out in her room. Both twins held their noses as the stench was a surprise, even to Chloe after Leys’ accident, and that soon turned to squishiness as squelching rang out with Miyu defecating into the seat of her pants. All that Chloe wanted to do to Illya happened to Miyu instead, with the bonus of thumbsucking too, as Chloe took note of that adorable babyishness. She had only prepared so much, and yet now that she thought of it, she could have gone much harder into all of this with babying her sister.
However, the current problem was that it wasn’t her twin sister with her panties currently loaded with shit, but rather the third magical girl of the trio. As Miyu continued to relieve herself by using her panties as a toilet, all the twins could do was stare at each other, although Illya was the less happy one of the pair. “You'd better be ready to take responsibility for this, you know. Now I know why Sella was complaining about Leys having an accident, since I see exactly who caused the kind of accident she had.” With her free hand, Illya pointed at her best friend, who still sucked her thumb, as a dumb smile was hidden behind her fist.
Alas, just as Chloe opened her mouth to bring up her brilliant preparation, Miyu interjected with a soft, “All done making poopies!”
Once more, the other two magical girls felt the whiplash of the most serious girl of the trio acting like an incontinent infant, although Chloe braved the stench by closing the distance between herself and Miyu. “What a good girl! Why don’t we get you into something more appropriate for your big butt?” While Illya mouthed her confusion to her sister, the dark-skinned twin knew she had to take control of the situation, and thus she led Miyu to the side of Illya’s bed before directing her attention back to her sister. “I have to go grab a few things, so can you strip Miyu down and lay out a towel so that I can clean her up when I get back? It’ll only be a few minutes since I have some supplies ready in my room.”
For a moment, Illya looked as if she were about to question her sister about those aforementioned supplies, although her pale face grew red instead. “St-strip? Like down to her pan-"
“Naked."
“B-b-but…”
"Yes, right down to her butt. Hurry and get on it before Miyu makes the clean-up so bad that even Mama would have trouble.” Chloe hurried past the stunned, blushing Illya, although her own tease bugged her as she headed to her room. She didn’t know if Mama would actually make it home for their birthdays, but the maids would be back from their errands in a few hours now, which meant Chloe had to fix Miyu’s hypnosis by then. However, that also gave her some time to use Miyu against her twin, which the dark-skinned loli had already given some thought to as she grabbed the changing supplies and the partially opened bag of diapers from her room. Time was ticking, and she didn’t have a moment to spare as she picked her pace back up with a hurried crinkling to Illya and Miyu.
And yet, in the few minutes she was gone, Chloe blinked a few times at the scene unfolding on the edge of Illya’s bed. Instead of Miyu lying on a towel with her shit-laden asscrack exposed to the twins, the naughtier loli was the least lewd girl in the room as a nude Miyu was in the process of stripping Illya. And Illya was just, uh… whimpering and going along with it, huh… All Chloe could do was watch and stare at the scene unfolding in front of her, almost as if something partially short-circuited in her now that she assumed the caretaker role. As soon as Miyu finished getting Illya’s clothes off, it was only then that Chloe cleared her throat. “And what do I find here, hm?" That stern maturity almost sounded foreign to her, and it must have to Illya as well as her twin snapped to attention.
Miyu, on the other hand, seemed to be too hypnotized still to be surprised, past her beaming proudly at having disrobed Illya. “Butt naked like you said!" Whether she was talking about her own filth-covered ass or Illya’s bare, white butt in front of her, Chloe wasn’t entirely sure.
What Chloe did know was that she tossed the changing supplies and bag of diapers into the middle of the room before marching to the closet and grabbing a second towel. “You’re still such a good girl, Miyu. Hopefully, Illya can follow your lead.” With a glare toward her twin, Illya cringed on the towel before turning away, almost surprising Chloe. She knew Miyu was a weakness of Illya’s, but Chloe expected to utilize the raven-haired girl more sexually against her twin instead of like this.
How she could exactly describe what this was was another story, but Chloe knew she was in charge as she laid the second towel on the bed next to Illya, and Miyu happily got on top of it. For as pale as either girl’s rear was, Illya wasn’t the one who pooped herself before, so Chloe paid more attention to Miyu while her twin used her hands to cover her crotch. Grabbing the supplies, she pulled out some wet wipes and got to work on Miyu’s butt. Luckily, since the mess hadn’t been sat on or squished, most of the poopiness was superficial and wiped away almost immediately. Within a couple of minutes, Miyu’s rear was as clean as Illya’s butt, leaving both girls ready for their diapers as Chloe moved onto the next step.
After cleaning up the wet wipes and tossing them in the trash, the dark-skinned loli waddled back to the package of diapers to retrieve two pairs of padding, and only then did Illya finally speak up. “Chloe, don’t you think this is going a little far? I know Miyu had an accident, but since you’re diapering her, she wants me in one too. Do you really want to see your older sister in a diaper?" Well, did she?
That was a pretty intriguing question posed to Chloe as she brought two diapers over to the bed and set them between Illya and Miyu, along with the opened bottle of baby powder. However, she took issue with how Illya framed the question. " Don’t you mean to ask if I want to see my baby sister in diapers? After all, you’re the naked one, lying on the bed next to a girl who just pooped herself. To me, you look more than ready for a diaper, and wouldn’t you want to be Miyu’s padded playmate?” This was when she could use the third magical girl against Illya, even if Miyu had been reduced to sucking her thumb waiting for her diaper.
Almost impatiently, too, as Miyu started kicking her legs and fussing. “Illyaaaa, just get your diapee on already! I wanna play!" That was, uh… Almost a little too perfectly on queue, although Chloe didn’t have too much time to test her hypnosis theories. Maybe, just maybe, she’d try to do this with Miyu again, but for now, Chloe turned her attention back to Illya.
Specifically, Illya hesitantly took one of the diapers next to her and offered it to Chloe. "Can you… please change me into this diaper." The whole time, Illya couldn’t even look at her because of how red her face was, and Chloe savored every moment of it.
“What else is a big sister for other than diapering her little sister?” Without giving Illya a chance to rebuke the sisterly status change, Chloe grabbed Illya’s ankles and lifted her butt enough to slide the diaper underneath her rear. Part of Chloe wished she had managed to get cuter diapers for them, but this last-minute plan left her to get small, plain white diapers that’d just about fit them. For as much as Illya tried to cover her pussy before, the fight was gone from the girl as Chloe spread her legs to sprinkle powder over her crotch. She almost thought about teasing Illya down there, but the lack of resistance wasn’t as fun, leaving Chloe to spread the powder around softly. A little more powder was added near her butt, and Illya grumbled when Chloe’s hand rubbed her butt, but it almost surprisingly didn’t go any further than that.
Finally, Chloe pulled the front of the diaper between Illya’s porcelain thighs and got to work on the tapes. Bottom left, bottom right. Top left, top right. And then a little bit of fitting here and there around the leak guards. Soon enough, Chloe patted the lingering baby powder off of her palms and looked down at Illyasviel, swaddled in nothing but a pure white diaper. It really did look so fitting for her…
Chloe was so lost in thought at the cuteness of her padded twin that it took Miyu’s voice to bring her back to Earth. “Me next! Me next, please!" Miyu was pretty good at playing the part of a good girl, likely due to her instructions beforehand. A monster of her own making, but Chloe grabbed the other diaper and got to work on the raven-haired girl.
After having changed Illya into a diaper, Miyu’s change was as simple as could be, as Miyu giggled all the while. In but a few moments, Chloe patted the front of Miyu’s diaper with a satisfied, “All done~ Look at how adorable you two are!" For a moment, Chloe held some pride over the fourth diaper changed by her hands, although a grumbling from Miyu’s stomach attracted her attention. Oh, huh, that’s something she didn’t reasonably expect. “Geez, if only Leys were still here. She has more of the udders to feed you than I do, but I’m sure I can scrounge something for you.”
And yet, Chloe saw a dangerous glimmer in her twin’s eyes as Illya grabbed her wrist. “Come on, you’re the big sister, right?” For once, the dark-skinned loli was the scared one as she felt a little bit of something damp trickle out of her, and not the naughty kind either. All of a sudden, Miyu followed suit, and Chloe found herself pulled between them. The pair of magical girls tossed the big sister onto the bed, of which it was Illya’s turn to do the stripping as Chloe’s tank top was removed with one hand while her other hand pinned the pair of dark wrists.
Typically, Chloe was more than happy to expose her breasts as a tease, but something felt different when Illya forced this situation upon her. Not only that, but to her other side, Miyu crawled next to her on the bed, and it was mere moments before the raven-haired girl’s lips were around her right nipple. Instantly, Chloe’s thighs squeezed together as well as they could despite this crinkly situation, of which a blush spread across her face when Illya finally noticed that she and Miyu weren’t the only diaperbutts in the room. “Oh my gosh, you wanted to be the big sister, but you’ve already been wearing a diaper!" Chloe wriggled and fidgeted to escape her position as Illya toyed with the waistband of her diaper that peeked above her shorts.
After all of her posturing, the dark-skinned, diaper-wearing loli couldn’t believe Illya found out her secret so easily before she could fully assert her dominance. From the moment Miyu arrived today, all of Chloe’s plans began to go awry, including now as Chloe barely withstood Miyu's suckling, while Illya’s hand unzipped the front of her shorts. On any other day, she would have imagined herself in Illya’s position instead, but Chloe squirmed on her sister’s bed as her panting grew heavier. “It was… it was only for testing…” Well, testing her personal interests, although Chloe found herself put through the wringer in terms of potential fetishism as she couldn’t tell if she was more embarrassed or turned on as Illya rubbed the front of her slightly damp diaper.
“Testing for what? To see how much of a baby you were while you tried to hypnotize me for my birthday? You’re even a little wet already…” Sadly to say, Chloe couldn’t even try to play it off as a naughtier kind of wetness at first, since she had piddled herself a touch before. However, since Miyu was nursing from one nipple while Illya moved her hands from her wrists to her other breast, the other kind of wetness was blooming as Chloe’s thighs squeezed against the thickness of her diaper. The feeling of needing to pee was building up in her, although Chloe couldn’t tell if she actually needed to pee or if the dual-sided teasing triggered a different reaction in her, one that Illya clearly noticed as well from her wriggling. “If you need to use your diaper, just go ahead and use it already. Just make sure to say that you’re using it like the baby sister that you are~”
“No, I… I’m still the big… b-big baby, aaahhh…” Chloe’s groans turned to moans as her thighs seized one final time, and relaxed as her bladder couldn’t hold out any longer. Something naughtier squirted out of Chloe, but her urine quickly supplanted that wetness as she filled out the front of her diaper against her twin’s hand. Illya didn’t stop rubbing the front of her diaper in the meantime, continuing to toy with her, all while Chloe noticed one of Miyu’s hands moving between her own thighs out of the corner of her eye.
More and more pee rushed out of her to flood her diaper as the brown-skinned loli’s bladder wasn’t even trying to hold back anymore, and Chloe’s body went limp aside from the occasional twitch of pleasure from such a strong, gushing release. Peeing so much was a much wetter kind of orgasm than she could have expected, and maybe more than just wet, as the weakness of her body prevented her from stopping a small fart from escaping her rear as well. As a whimper escaped from Chloe, Illya further urged her to let go. “Come on, you already admitted to being a big baby, so be a good girl like Miyu and use your diaper like a good girl~” Chloe’s cheeks burned as red as the color of her usual coat, but she didn’t have the strength left in her to resist the log of shit spreading her asscheeks.
The little diaper-wetter’s toes curled as she felt the crap pushing out into the seat of her diaper, already mushing between her big loli butt and the bedding underneath her as her bowels gave up similarly to her bladder. A particular smell of poopiness lingered in the room from cleaning Miyu’s mess before, but Chloe’s stinky accident supplanted that stench as she felt the bulk of shit in her padded undies. Perfectly in time with her messing, Illya shifted to straddling her thigh before pulling Miyu onto her other thigh, leaving the weight of two little girls in nothing but their diapers to further smush her poopiness against the bed.
While Miyu barely took a momentary pause from suckling while moving over, Illya took her place on Chloe’s other nipple, as the dark-skinned diaperdumper wasn’t sure if she was meant to be the caretaker or baby between them. On one hand, both Illya and Miyu nursed from her nipples despite the depressing lack of milk from her petite breasts, although just the sensation clouded her thoughts from the pleasure. And on the other hand, she was the only one between the three of them blowing out her diaper as- oh g-geez…
Talk about perfect timing… While Chloe lay defeated on the bed in her soaked, dirty diaper, the top of her thighs suddenly felt warm as quite a mushy sensation burst out against either thigh. Not just one girl, but both of her fellow magical girls were blowing out their diapers while straddling her, further confusing Chloe about her role in this situation. At the very least, she got a temporary break from the pleasurable assault on her flat chest as both girls strained to shit themselves atop her, although Chloe did cringe a little as Illya made sure to add, “Oopsie, looks like you’re not the only baby here!~” So much for Illya’s usual declaration of being the older sister, but maybe this was a lesson to Chloe about not messing with that role in the future.
However, when both girls finally finished up, and Miyu added a soft, “Done with poopies… again…”, all three of the magical diaperdumpers panted from the exhaustion of the entire situation. Chloe’s mind still spun from all of the excitement, especially as Illya and Miyu relaxed against her petite bosom, their soft breaths tickling her stimulated nipples. If Chloe hadn’t been so young, she almost wondered if so much suckling might’ve actually caused her breasts to produce some milk, although she was probably still a few years off from then. And yet, after such a good incident as this, she could easily see the three of them doing this together a few years from now if everything went all well as it could. Well, aside from the obvious issue…
“Um, Chloe, you do have a way to break Miyu’s hypnosis, right?”
Ah, that was the exact question the dark-skinned pottypants wasn’t hoping to deal with, although it had to come up sooner or later. “It’s supposed to wear off at some point, or I think it did with Leys.”
“Eh, you think? You know why she and Sella went to the store today, right?” A shiver went down Chloe’s spine upon hearing those words from Illya, although she tried not to fidget too much since she noticed Miyu nodding off against her chest. Illya, on the other hand, rolled more to her side and took her twin’s sister as confirmation of not knowing. “Leys messed herself in her sleep after her accident yesterday, so Sella took her to get diapers.” That was precisely what the dark-skinned loli didn’t want to hear, as she shifted her arm to cradle a sleeping Miyu against her.
A different kind of clamminess than the wetness in her diaper came over Chloe, although she did remember talking to Leys before the maids left. “She seems like she was back to normal this morning, so maybe most of the hypnosis wears off? Plus, can you really blame me too much if Miyu is so adorable in diapers like this?” The raven-haired girl softly sucked her thumb as she rested against Chloe, blissfully unaware of the effects of the hypnosis on her body. With a look back at Illya, Chloe saw her twin turn away with a blush and knew she had flipped things back on her.
“F-fine, maybe it won’t be so bad. Just say that it’s due to magical girl stuff or something, I don’t know… Or m-maybe…”
“Hm, maybe?” That hesitation piqued Chloe’s curiosity. “Go on~”
Chloe’s urging quickly caused a pout on Illya’s face, although the fairer-skinned diaperdumper continued. “Maybe it wouldn’t be so bad for Miyu needing diapers if we all wore them together. Sella might have to put in a bit more work, or we can promise to change each other, or just something, and I’m sure we can get Mama to go along with it.” Oh yeah, Mama… the wildcard…
The dark-skinned loli knew Illya presented a gamble, although the feeling of her soggy, mushy diaper swaddling her waist made it tough for Chloe to disagree. “We’ll just have to see what Mama says then, although at that rate, we’ll both end up as baby sisters together, you know. Can you accept our mutual loss in exchange for getting to wear diapers more often, if not from now on until Miyu doesn’t need, or maybe even want, to wear them anymore?” If Mama got involved, that possibility was very realistic, if not a more babyish situation, but Chloe didn’t want to deter her twin too much, potentially.
And yet… “You don’t think Miyu would come around to diapers if we’re both also wearing them?” The smirk on Illya’s face told Chloe all she needed to know about her twin’s influence, or maybe it would be more accurate to say her big sister’s influence. As much as Chloe tried to assert herself as the older sibling through her trickery, Illya made it more than clear to her who the real big sister was.
Needless to say, Chloe felt humbled by her sister. However, that didn’t entirely quell her snarkiness as she asked, “Well, if you’re going to be the most mature baby among us, I guess you can be the one changing my diaper this time. After all, what else is a big sister for other than diapering her little sister?” The smirk on her face only grew wider as she saw the realization of such messy responsibilities dawn upon Illya, meaning Chloe von Einzbern had a new way to torment her twin sister. What a perfect birthday gift for her!~