Higurashi half-shot

The monotony of today's math class was suddenly interrupted by the green-haired Sonozaki Mion.
"Can I be excused, please?!"
Her voice trembling, the girl pleaded, squirming in her seat. The rest of the class fell silent as they turned towards her, watching her sweat and blush.
"Is something the matter, Mion-san?"
There was, and those who knew were all chuckling to themselves behind their hands.
"N-No, I'd just like to be excused..."
Mion couldn't dare to face her teacher - staring into her blue eyes while lying felt like such a betrayal. Instead, she firmly locked eyes with her desk, watching the beads of sweat splash onto it.
"There's only more class after this, can't it wait? I'd hate to dismiss you this late-"
"Sorry, but I really need to go..."
Mion couldn't believe what words she was uttering, much to the entertainment of her dear group of friends, who were in the know about what was happening. Satoko chuckled to herself, enjoying watching the eldest in their group embarrass herself. That's what you get for making me wear that collar, she thought.

Chie-sensei saw the urgency in Mion's eyes, sighing as she nodded her head. Everybody watched as Mion bolted out of the door, but curiously, going right instead of left towards the main entrance. They whispered to each other, coming up with dozens of conspiracies as to where the girl was headed. Of course, someone reminded the group that the bathrooms were on the right, then watched the whispering turn into laughter. Chie immediately stopped the mocking, trying her best to steer the class back into order. This brief moment didn't last long, as soon enough, the other Sonozaki raised her hand.

Her mind was spinning so fast, her body aching, she forgot to count heads inside the classroom before running to the bathroom. Pressing her back against the door, the Sonozaki girl wiped the sweat beading on her forehead before tugging at her pink skirt's waistband.
The diaper between her thighs did little to boost her confidence, but the dash from her classroom to here left her winded and numb downstairs, fearing a leak from her bloated bladder. Mion carefully unclipped her skirt,   holding it together with her hands as she shuffled towards a stall, the sound of crinkling ringing in her ears. The neighbouring stall was occupied - meaning she had to stand there and stew in an embarrassing diaper for just a bit longer.
She went inside, releasing her skirt she held with a grip. Now with nothing to hide her bulky diaper, the girl could only wait as she stretched her white shirt halfway down to her butt, squirming in place. Undoing the tapes meant letting out that horrible ripping sound, which would definitely kickstart gossip from the girl in the other stall.

The pressure in her belly pressed harder and harder, but Mion had to endure the pain until the other occupant left. It didn't help that she could only stare at the toilet, beckoning her to come. This damn punishment game went way too far; not even Rika was forced into diapers when she had to cosplay as a baby. These games shouldn't ruin someone's whole reputation, even if Keiichi was now a pervert in everyone's eyes. Curse him! Him and his tenfold revenge...

Soon enough, the door to the bathroom flung open with a creak, sending shivers down Mion's spine. There wasn't a sound she didn't hear as her senses kicked into overdrive. Every step the new girl made pounded in her ear, each heartbeat inside her chest feeling like a strike from a hammer. All she could do is pull her skirt up to her knees, trying to hide it from view.
The handle on her stall started to turn and shake. Her blood went cold as the person behind started leaning into the door before Mion could meekly let out a laughable warning.
"H-Hey, occupied!"
Now her bathroom neighbour knew her identity, making it even easier to start rumours. Immediately, the girl scrambled to pick up her skirt and bring it back up to her waist, sliding it up her legs when suddenly-
"Yeah, I know! Open up.~"
That voice was from no one other than her twin sister, the other green-haired Sonozaki; Shion.
Mion didn't even get a chance to respond before she saw a credit card poke through the seams, sliding down towards the lock. With just one click, the door flung open, and Shion stood there with her hands on her hips.
"Ha - I knew you'd try and cheat!"
There were so many insults Mion wanted to scream at her sister; she blurted them all out at once as the other Sonozaki entered her stall and closed the door behind her.
"Shouldn't I be the one mad here? Now I have to stay and make sure you use your diapers..."
"Shion... Aren't you also wearing them? Why don't we just make a sisterly pact here and-"
"Nope! No can do! Because..."
Shion shamelessly lifted her skirt, showing off the same diapers Mion wore. Hers were, of course, already damp and swollen with pee from an earlier wetting.
"You're unbelievable, you know that?! You're supposed to be the older sister here!"
Those words meant nothing to Shion, who giggled at her sister's rage. With Shion here, the chances of a clean getaway were trimmed down to zero. The longer they wasted time here, the more suspicion it would rise with the other students. Not to mention the girl next to them was listening in, saying nothing. Without any warning, Shion pressed her hand into Mion's diaper, squeezing the front padding thoroughly. Her sister wasn't going to budge, so Shion had to coerce her by playing rough.

Shion closed the gap, pressing herself up against the other girl - who tried her best to escape her sister's grip. The green-haired girl tugged at her sister's shirt, making sure it didn't cover any inch of her bulky diaper. All her sister could do was moan and squirm as she felt Shion's hands rub all over her body before grabbing her hips and pushing her further towards the toilet.
"S-Shion? What are you doing?"
"What? It's your first time, right? You should do it on the potty!"
"F-First and last time..."
Mion said under her breath, letting Shion guide her over. Just before sitting her down, Shion yanked at her sister, forcing her to turn around. It immediately dawned on her, her dear sister wanted a full view of the chaos about to unfold. She begged, almost on the verge of tears. Shion ran her fingers against her back before pushing her down onto the toilet. What a sight, the future head of the Sonozaki Yakuza, whimpering with her diapered butt in full view, about to have an accident like a little child. She turned her head and locked eyes with Shion, who squatted down and watched with her hands on her face.
"Go ahead, stinky - we haven't got all day!" Her sister hissed at her, tracing a smile into the folds of the white diaper. She'd occasionally stop and poke, hoping it would encourage her sister. Yes, Mion was happy to be spending time with her twin, but not like this.

Now that her body was in a comfortable position, Mion started relaxing her tense muscles. There were too many thoughts inside her head swirling around, screaming at her to stop.
She dug her fingers into the white porcelain, pushing her feet into the tiled floor and moaning as her head hung low. Immediately, her full bladder started squeezing the pee out of her, quickly filling up the front of her thirsty padding that quickly soaked up every drop.
Mion bit down her teeth, grinding them as her muscles loosened and air from her full bowels escaped, the sound muffled by the diaper tightly wrapped around her butt, also helping reduce the stink. After that, she felt something pushing against her butt; before her guts started to release their contents into her white diaper. Shion cooed at the sudden bulge forming from her sister's butt, watching it tent out the diaper. She touched the bulging part with her index finger, pressing into it and squishing her sister's diaper, enjoying listening to it crinkle. The first half of the mess was painfully solid, not something fun to pass, especially for a first-timer. It was a struggle for Mion, whose head was spinning from the strain of pushing. Suddenly, after another push, the mess turned much softer and warmer, filling up the empty space left between the solids inside her diaper. Shion giggled at the squelching sound coming from her sister, enjoying the show. The two lines serving as wetness indicators had long since turned a sickly green, making sure there was no confusion to the state of Mion's diaper.
"Wow, sis, you sure had to go! Have you been holding it since this morning?" The other twin cooed, further poking and squeezing her sister's grossly bulged diaper.
"S-Shut up..."
The truth was, she's been holding it in since yesterday. Her lips were trembling as she felt her diaper being fondled so aggressively. Random squeezes made sure to smush in any larger clumps, sticking the diaper against her skin like glue. No wonder babies cry incessantly - Mion even let a few tears roll down her red cheeks.
"Good job, sis! I knew you'd do it."
Shion wrapped her arms around Mion, making sure to tightly squeeze her twin sister. Here, Mion vowed to think of a punishment game that's a hundred times worse, making sure to chisel the loser's fate in stone.
"Can I go home and get changed now?" Mion begged, barely able to stand up because of her trembling legs.
"Hmm? Get changed..? We still have class, y'know?"
Mion's blood ran cold once again - she almost fainted, falling down onto her knees, her thighs unable to close because of the bulk. "Isn't that right, Rika~chan?"
On the floor, Mion looked to her right, face-to-face to a familiar smile and blue eyes peeking from under the wall.
"Mii- Nipah~☆!"
Even the smallest girl from their group, almost a full five years younger than her, giggled at Mion. A few flashes from a camera quickly turned her vision white, as she knew these memories would remain for ten more years. Here is when the waterworks began, Mion fully bawling into Shion's shoulder as the other two laughed harder, all while her twin continued rubbing the back of her diaper. Shion urged her sister to calm down, telling her that people will forget all about it.

Mion's neck suddenly felt extremely itchy.