(ABDL, SOIL) DRABBLE - Minamoto-no-Raiko

Raiko gets a chance to indulge in a secret hobby, one that is quite messy and childish...

Series: Fate/Grand Order
Characters: Minamoto-no-Raikou
CW: ABDL, Ageplay, Farting, Hypermessing, Hyperwetting, Implied Pants Soiling, Diaper Soiling, Baby Talk
All SUBJECT characters depicted are 18+.

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The heavy door clicked shut with finality, its echo drowned beneath the throb of Raikou’s heartbeat. She stood frozen, her back pressed to the cold metal as if it alone could anchor her. Each breath came in shallow, quivering draws, her large chest heaving against her attempt at stillness.

At last—solitude and privacy.

No Servant nor her cute Master around her to ruin this special moment.

Her trembling fingers hovered at the curve of her stomach before drifting lower, slow and reverent.

“Mmm… finally some time for myself…” she whispered. Her hand spread across the gentle softness of her midsection, fingers sliding downward in a motion both familiar and forbidden…

—Until her fingers brushed lower and a faint, crinkling sound was made beneath the fabric.

If anyone were to listen closely around the matronly woman, they could hear every slight movement from Raikou coaxing soft, rhythmic rustles and crinkles that whispered through her room.

In fact, if anyone were to LOOK closely at her, they’d see a thick bulge pressing from the crotch of her purple bodysuit, curving firmly over her rear and hugging her hips and thighs, its bulk just enough to subtly part her legs.

—With all those signs, it couldn’t be hard to guess that the voluptuous, violet-haired woman was wearing a very thick diaper underneath her clothes.

Raikou exhaled slowly, a faint shiver tracing her spine as her hands pressed over the thickly padded shape that cradled her wide hips and generous rear beneath her suit. She smirked, shifting just enough to feel the plush resistance between her thick thighs, absurdly comfortable and warm.

Raikou shifted again, pressing her palms gently into the soft bulk as her mind was already turning toward what came next. The pressure inside her was mounting and churning, and she didn’t intend to resist it. The anticipation just made the release a whole lot better—and bigger~

—Raikou remembered where it all started.

She’d been young then, wandering alone beyond the temple fields on an overcast afternoon. She had no idea she would discover her ‘hobby’ by accident. She’d skipped the morning latrine, assuming she could hold it.

But as the cramps hit and her body locked up, it happened.

With a loud, shameful squelch, the mess burst into her linen fundoshi. It was a thick, hot, and sticky feeling, as it piled up against her rear and oozed down along her thighs. Her bladder gave way seconds later, the rush of urine soaking fast and hot into the already ruined layers. The mixture of filth had pooled lower, moving with a sluggish weight between her legs, and dark stains had bloomed and bulged across the front and back of her hakama.

It was mortifying. Humiliating.

And yet, even as the flush of shame and horror crept over her face, something else stirred.

The effluence pooling between her legs, the feeling of her mess pressing against her undergarments, the idea that she had lost control of herself…

It was confusing how good it felt.

How right it felt.

There was something wonderfully naughty in the act itself, in knowing she had made such a large mess in her pants even by accident.

Somehow she felt like an adult woman and little girl at the same time: independent and unashamed of her own pleasure, yet mentally shrinking as she embraced the infantile comfort of what she’d done.

The contradiction shouldn’t have made sense, but somehow, it just worked. She felt proud, in a childish way, and relaxed in a way only a child could be: utterly pleased in her own mess.

…It never stopped. Even as she came into her own legend, carving through oni and monsters, she never forgot how that one accident that day slowly became a part of her. An accident that became a deliberate and depraved obsession that never stopped.

Alone in forests or behind the privacy of walls, she’d let go and fill her underclothes with bodily waste. How she grew to love the warm, sticky spread between her butt and thighs, and the slow, weighted bulge of her pants. With every naughty little session with herself, she felt her fascination deepening and her control weakening.

But it had consequences. She’d ruined dozens of her hakama, her robes, so many of her own. Cleaning them was a struggle, and when the smell lingered or the stains set too deep, she had to dispose of them, sometimes by burning them. The mess was bold, cleanup draining, and one mistake could tear apart the image and reputation she had.

That’s when she found the solution:

Diapers.

—Or at least, what counted as adult diapers back in her day.

Diapers were something that also came to mind when she had started her “hobby”, thinking of how infants were swaddled in layered cloth and padded with moss or mulberry paper. So, Raikou had adapted this method for her own adult use, and found success when her makeshift diapers held everything without the need for cleaning up messes and risking exposure.

Messy wet pants shifted into messy wet diapers. She began to enjoy the way they hugged her body. She liked the sound they made when she walked. She liked the softness and thickness between her thighs. Soon, even when she didn’t need to go, she wore them. She was addicted.

And yet over time, it didn’t just stay with her indulging in soiling herself.

She was already finding childish joy in filling her garments, so why would it be any surprise that she started to find childish joy in being a child?

That she soon wasn’t just acting on instinct, but also on desire?

That she started to find joy not just in being messy, but in being little?

Raikou would crawl across the woven mats on all fours, hands curled and giggling softly as she babbled into the quiet. Sometimes she wore only her thick diaper, other times babyish clothes. She stacked blocks, shook rattles, kicked her feet while humming, and often sucked her thumb, drooling and eyes half-lidded in bliss. And when the moment came, Raikou would fill her diaper with plentiful waste, spreading warmth and bulk in large amounts.

When she was summoned to Chaldea, dragged through time and space to fight for humanity's future, her obsession didn’t just survive the transition.

It flourished.

Chaldea had offered her more than just purpose. It gave her freedom. Resources. Endless possibilities. In this sterile, impossibly advanced facility of the future, no one could stop her from exploring the deepest corners of her own desire.

If there was one thing she found that was a godsend to Raikou, it would be something as overwhelming as the internet.

A web of knowledge and desire, it was more arcane than any magecraft she had ever encountered in her old life.

At first, she barely understood what she saw. The unfamiliar slang, the dizzying flood of images, the rapid chatter of anonymous voices layered in digital static. It felt like stumbling into another world. A secret one.

But a curious, intrusive thought had tugged at her: Might this strange new world have anything that reflected her own shame? Tentatively, she had typed the words she never dared speak aloud.

—And it answered, with open arms and countless voices.

ABDL forums, fetish blogs, anonymous chat rooms brimming with stories and confessions. Raikou devoured them all, reading post after post from others with electric excitement who relished in the same things she did.

The internet had opened the door, but it was only the beginning. With Chaldea’s vast resources at her fingertips, Raikou realized she could go far beyond reading. She had the means to make her private world real: supplies, tools, discreet help. And with the limitlessness of magecraft, any of Raikou’s naughty, padded fantasies were possible.

She placed her orders anonymously, and no one batted an eye at the sealed boxes left outside her room. Diapers, bottles, powders, and other custom-made items quietly crafted by other Servants who never asked questions. In Chaldea, where the unusual was routine, unopened boxes were a phenomenon that slipped by unnoticed if it wasn’t asking for attention.

—And now, here she was. Alone in her quarters, trembling as anticipation coiled in her gut. Raikou gave her padded crotch a slow, deliberate squeeze, her palm sinking into the plush bulk beneath the snug tension of her bodysuit. The thick diaper answered with a noisy, satisfying crinkle, the kind that tickled her ears and sent a thrill up her spine.

"Mmm… this one’s a lot thicker and crinklier~" she cooed, playful mushing the bulge pressing between her thighs. “Poofier than usual, too… and sooo comfy! Mommy might not want to change out of this one anytime soon!”

After a few more indulgent squeezes, each one deeper than the last, Raikou caught herself and let out a quiet chuckle.

“Ufufu~ Mommy will never get anything done at this rate,” she muttered, giving the padded curve a light pat. Straightening up, she began to make her way to her dresser, her thick thighs parted just enough to turn each step into a subtle waddle. Her hips still swayed with grace, but the soft bulk between her legs was impossible to miss.

After reaching her dresser, Raikou knelt gracefully and pulled out the bottom drawer to place it on the floor. Her fingers traced a tiny glyph burned into the corner of the exposed bottom shelf, and with a quiet hum of mana, a hidden compartment slid open. Beneath the drawer’s false base laid her most sacred indulgence: a private nursery in miniature.

Stacks of thick, pastel-taped diapers sat folded in neat rows, their cartoon prints peeking out. There were oversized pacifiers, animal-shaped teething rings, baby bottles etched with moons and stars. Quilted blankets lay tucked at the back, faintly powdered in scent. Wipes sat in soft-colored cases that hummed when opened, alongside jars of ointment and tins of lavender-scented talc.

Lined up in an ornate, rune-lined rack were a half-dozen medicinal bottles, each a different color and texture. Their labels were minimal, marked only with alchemical glyphs and glowing symbols. Each bottle shimmered faintly under the compartment’s soft, warm light.

Raikou’s eyes drifted across the lineup. Some were blue bottles, cool and pearlescent, for drowsiness and sleep. Others were faintly swirling purple phials that induced slow-acting, but potent mental effects.

And there, nestled at the center, sat a couple of green bottles.

Raikou reached for the green bottle with reverence, cradling it in her palm. The liquid within glowed with a soft, mossy hue, faint bubbles swirling in its thickness. Barely sweetened, yet its effects were legendary: one sip and the drinker’s bowels and bladder would swell, and their body would grow numb and loose, unable to resist release. It was designed to magnify everything, and each release would come in wet, noisy bursts.

Frequent and shameless, just the way she liked.

Her fingers curled tighter around the bottle as she remembered the feast she’d savored earlier. Every bite had been taken with this moment in mind. Every gulp was in preparation. And from that, she could tell this was going to be… massive.

Raikou’s fingers trembled with anticipation as she twisted the ornate lid free. A soft pop echoed in the quiet, and the thick, green liquid inside shimmered faintly—dense, syrupy, and streaked with glowing flecks of magic.

"Mmmn… just like before," she murmured, voice warm and velvety, as if speaking to a cherished secret lover. She raised the vial to her lips, letting the viscous fluid roll past her lips.

The taste hit fast, a rather syrupy, overly sweet, and artificial taste, like spoiled nectar. But Raikou accepted it without hesitation, the thick liquid crawling down her throat and leaving behind a slow-spreading warmth.

As she lowered the empty bottle with care, the aftertaste clung to her tongue, the room seemed to pause around her, as if waiting for what came next.

—Then a squelching, creaking groan resonated from her belly that filled the room.

“A-ah…” she breathed, voice low as her stomach groaned in protest and overwork.

Her bladder throbbed with phantom weight while her gut twisted in slow, coiling motion; not painful but relentless, like holding back a flood that wouldn’t wait. She stood still, breathing unevenly, every second heavier, her body clearly preparing for something big and unavoidable.

Raikou’s fingertips traced soft circles over her taut belly, her touch light and rhythmic, as if petting a restless baby’s tummy. Her legs gave a little wobble in anticipation, thighs quivering with the pressure and promise of release.

With a breathy hum, she let herself sink into a deep squat, knees bent wide, arms resting gently on top of them. Her thick thighs spread to accommodate the position, and as she leaned slightly forward, her ample breasts pressed against her legs, squishing softly. Her padded rear jutted outward just enough to nestle the thick diaper into position.

"There, there…" she whispered, her tone sugary and indulgent, laced with playful scolding. "Mommy’s tummy’s all full of yucky stuff now, hm? Gonna make big, big messies like a good girl, yes she is~! And ooh, such naughty wetties too, all sloshy and warm in her diapee… just like baby likes."

Raikou giggled softly as pressure built low in her gut, each subtle shift making her thighs twitch while her belly gurgled louder. She rubbed it gently, not to resist but to soothe, knowing better than to rush. This was about letting go slowly, easing into it without force, just breathing deep and allowing her body to soften as the bubbling inside readied itself to spill free.

PPPPFFFFFRRRRRRRRRRBRBRBRBRBTHTHTHHT!

The sharp, blaring trumpet tore through her quarters, echoing off the walls like a brass horn blown too close to the ear. Raikou only smirked with flushed cheeks and a bit lip, her expression dripping with naughty satisfaction even as her release of wind petered away.

“Ara~ Such a noisy gassy tum-tum,” she sang sweetly, voice bouncing with childish lilt. “Mommy’s makin’ all the rude sounds today, huh? Such a naughty tooter~!”

As if to respond to this, another burst of gas slipped free from her without warning, muffled yet far more vulgar. Her thick diaper drank in the noise, but it left nothing to the imagination. The pressure in her belly surged again, her core tightening with that giddy, unbearable fullness.

Raikou let out a high-pitched giggle, silly and shrill, something nobody would ever expect the motherly woman to let out. “Fufufu~ Mommy’s so silly today… all full of toots and messies~”

Her hips rocked slightly, knees dipping as another pressure wave pushed down, her belly bubbling like a cauldron. Her breath caught, eyes fluttering with anticipation as she instinctively welcomed the next part.

BBBRRMPFT—SCHHHHRK-SQRRBLT!

The next burst of gas gave way to a wet, loud release as mud like warmth rapidly flooded the thick padding beneath her. Her poofy diaper crinkled and sagged with each wave, slowly stretching to hold the mess as it spread across her big backside, the swollen bulk growing heavier and denser with every moment.

She didn’t flinch. She didn’t hurry. She only just breathed, her eyes dreamily half-lidded and her face scrunched in a pleased pout as her body gave itself over completely to the release. Her legs wobbled beneath the growing pressure, knees quivering under her weight, but she remained steady.

PSSSHHSSSSHHHHHHHHHHHT!

And as her bowels loosened, her bladder gave way at the same time. A torrential warmth surged into her waiting diaper, flooding it with a hiss that melded wetness with weight. The liquid crept outward, filling every crease and channel of the padding, swelling the garment as it greedily drank her in.

The diaper swelled rapidly, ballooning more with each passing second as wave after wave of waste poured into it. Its size grew more outrageous as it puffed out in every direction below her, looking less and less like a diaper as she continued to flood it. The bulging diaper dipped lower with her bodysuit, thickening toward the floor like a swollen fruit.

And all Raikou did was smile.

A broad, breathless, drooling smile.

There was no embarrassment, no shame. Only the dizzying, shameful relief of literally pooing her brains out, her body all warm and tingly as she took in every single moment happening to her.

As the bloated padding finally pressed firmly into the floor beneath her, its growing mass forced her legs further apart with every sloshy shift. Her thighs were bowed wide now, the snug lower half of her bodysuit puffing outward with the strain, visibly distorting with each inch of expansion. How her suit didn’t rip was a miracle in itself, yet Raikou didn’t seem to care.

Her voice spilled out in lulling, babbled coos between low, breathy moans as her mind was on naughty baby overdrive. "Mmmh... Big poopies… Haaha… Naughty poopypants…"

Raikou’s stomach squelched loudly again above the sounds of messing and gas she was producing, the oni-blooded woman lightly grimacing as she felt a huge cramp moving down her stomach.

Without a moment of stopping, Raikou simply lifted her leg lightly, face scrunched in a grunt as a wet, sputtering BRRBLRBBRRPPFFT! burgeoned her waiting diaper with large chunks of solidus poo. The force ballooned the seat so quickly it rapidly lifted her feet off the floor.

“Buhlbbluh… hehe… poopiesh…” Raikou drooled out, her mind on cloud nine as she felt her ass vomit out more squelching gas and slimy manure. Even as that one load of waste finally ended and her flow returned to normal, her release kept coming, her exercise ball-shaped diaper continuing to grow.

Her mind floated in her own private heaven, her eyes glassy and mouth slack with mindless pleasure. The diaper bloated up around her like a growing bean bag chair, rising beneath her bottom and hips in soft, pulpy waves. She babbled nonsense through a dazed smile, little streams of drool slipping down her chin as her thoughts dissolved into mush.

Time slipped away as finally, the last tremors rolled through Raikou’s body and her movement came to a close. A whining, sputtering shart pushed out any remaining liquid contents of her colon into her destroyed diaper, joined by the trickling of urine petering out into the disgusting soup she made.

Raikou collapses onto the soft, bloated cushion around her butt. The diaper squelched beneath her weight, redistributing its warm contents across her hips and backside in thick, gooey layers.

She let out a long, steady sigh of contentment, letting herself melt into the mess she'd made. Mind finally clearing, her cheeks flushed as she glanced down. Her bodysuit stretched tight around the bloated padding, the fabric clinging to every bulge and curve.

“Honestly… I wonder why I could be so enamored by something like this?” she murmured, returning to her composed, normal self. “Anyone else would be appalled by the state I am in…”

Raikou’s thoughts drifted in the quiet that followed, tinged with a familiar melancholy: loneliness. She was right, nobody at Chaldea knew, and she doubted anyone would understand, let alone share in the strange, crinkly intimacy she held so close

It was all hers alone, like or not…

…

…

…Or was she really?

A stray thought licked at the edges of her mind: what if she really wasn’t alone? What if she didn’t have to be alone in this? What if she could share this strange joy with someone else?

Two certain people came to mind, two who were the most understanding and most empathetic people she had met in Chaldea. Two who happened to be her new adoptive children since her summoning.

—A fantasy began to bloom in her mind.

—Ritsuka and Mash.

—Both of them squirming in oversized, crinkly diapers, their faces red with embarrassment yet eyes showing intrigue. She imagined them toddling side by side, arms linked, making squishy little messes together like good babies.

—Her babies.

Raikou’s lips curled into a slow, mischievous grin, a plan forming and many ideas already taking shape in that terrifying head of hers.

She knew them the best. She had the confidence things would go as Raikou had predicted.

“Soon,” she purred, her voice rich with promise, “Mommy’s gonna have her sweet Master and precious Mashy-washy filling up their diapees together… side by side, just like perfect little angels.”

All three of them, together…

Being a nice padded family…

…But for now, she will wait a bit. Just a little longer. Because right now, she wanted to enjoy squishing into the diaper she filled up.

She nestled deeper into her bloated, crinkling cushion and closed her eyes, letting the warmth lull her. The calm was hers—for now. Soon, she’d have company…