[Hirose Residence, Living Room — April 12th, 7:14 PM]
---
"Are you really okay?"
Satō Shirō's voice carried the weight of a boy trying very hard to sound like a man. His jaw was tight, eyes flicking between Yoru and Riku with poorly concealed irritation. The smell of buttercream frosting and warm wax clung to the room, undercut by the faint cedar of Madam Hirose's incense burning on the side table.
She's MY girlfriend. Why is this guy hovering around her like some protagonist from a harem anime?
He wanted to say something sharper — wanted to grab Riku by the collar the way Bakugo might grab Deku and scream the accusation out loud. But today was Yoru's birthday. And Riku had been invited by Yoru herself. Shirō swallowed the bitterness like bile.
"Mm..."
"I'm fine."
Yoru's thighs pressed together beneath the hem of her skirt — subtle, deliberate, the motion of someone holding a secret against their own body. She walked with careful, shortened steps toward the wooden bench near the dining table and lowered herself onto it slowly. Too slowly.
The fabric of her pale blue skirt pooled over her knees. Underneath, her white thighs rubbed against each other in small, rhythmic motions — left, right, left — each shift an attempt to manage the persistent, maddening hum nestled deep between her legs. The vibrator buzzed at the third setting now, a low throb that pulsed against her clit in steady waves, and the dampness spreading through the thin cotton of her panties had already turned from a suggestion into a statement.
Don't clench. Don't clench. If you clench it gets worse—
"Daughter, are you feeling unwell?"
Madam Hirose Kaguya appeared at her side — tall, composed, her dark hair swept into a low chignon. The matriarch's eyes, sharp as a hawk's behind the warmth of her smile, studied Yoru's flushed cheeks. She smelled of jasmine hand cream and the starched linen of her blouse.
Yoru kept her legs pressed together, ankles locked. Beneath the skirt's coverage, her inner thighs were slick — a thin, warm trail of arousal had crept past the elastic of her underwear and kissed the skin just above her knee. Each micro-vibration sent a pulse radiating upward through her pelvis, tightening her lower abdomen in a way that made her want to curl forward and disappear.
She couldn't move too much. If her mother looked down — if anyone looked down—
"It's nothing. Just a tiny bit... I'll be fine in a moment."
She exhaled through parted lips. Slow. Controlled.
Breathe. Just breathe. Like Nezuko in the box. Quiet. Still.
After a few agonizing seconds, the intensity plateaued into something she could endure. The buzzing settled into the meat of her, a deep and constant companion rather than a sharp intruder. Yoru released a shaky breath, the flush on her cheeks dimming from scarlet to a warm rose.
If Riku turned it up again, she would break.
She was certain of it.
Her eyes searched the room — past her mother's concerned face, past Shirō's hovering posture, past Uta's half-interested gaze — and found Riku standing at the far end of the dining table, arranging plates with the unhurried calm of someone who had absolutely nothing on his conscience.
His fingers set down a porcelain dish. Adjusted the angle. Moved a fork one centimeter to the left.
He wasn't looking at her.
That bastard. He knows exactly what he's doing.
"Riku..."
Her voice barely carried — a threadbare whisper meant only for him. Soft. Pleading.
Riku's hand paused on a dessert plate. He turned, and the motion was easy, unhurried. One step toward her—
Shirō materialized between them like a wall.
"Yoru, if something's wrong, you can tell me."
He planted himself in front of her, chest puffed, shoulders squared. The posture of a guard dog who didn't realize the threat was already inside the house.
This absolute idiot.
Yoru stared at Shirō's earnest, clueless face and felt something between fury and despair coil behind her sternum. How was she supposed to explain this to him? Oh, Shirō, your friend put a vibrator inside me and he's been torturing me with it for the last twenty minutes. Could you step aside so I can beg him to stop?
The words she'd wanted to say to Riku — stop, please, you've gone too far — died in her throat, killed by Shirō's unwitting intervention.
Shirō grinned, oblivious and eager, like a golden retriever presenting a chewed-up shoe.
"Yoru, let's light the candles!"
She had no choice.
"...Sure."
Before standing, Yoru pressed her thighs together one final time — a firm, deliberate squeeze. The friction dragged the soaked fabric of her panties against her swollen clit, and a fresh wave of heat bloomed across her face, painting her cheeks a deep, damning pink. The cotton was ruined — completely saturated, clinging to her folds like a second skin. If not for the skirt's merciful drape, the dark wet patch would have been visible to anyone standing close enough.
God. I'm dripping.
She stood. Each step toward the table was measured and careful, her inner thighs sliding against each other with a slick whisper she prayed no one could hear.
---
Two birthday cakes sat side by side on the white tablecloth.
The first was Riku's — a towering twenty-four-inch confection, three tiers of ivory fondant decorated with hand-piped cherry blossoms and edible gold leaf. It looked like something out of a Food Wars spread, the kind of extravagant centerpiece that commanded an entire table's attention.
Beside it, almost comically, sat Shirō's offering: a modest six-inch cake from the bakery two blocks over. Simple white frosting. A single ring of strawberries around the edge. Two number candles — a 1 and a 9 — poked out of the top at slightly uneven angles.
Shirō stared at the size difference. His smile didn't waver, but a muscle in his jaw twitched.
Seriously? Who brings a cake that big to someone else's girlfriend's birthday? Is he trying to one-up me? This isn't a shōnen tournament arc—
"Yoru, I'll light the candles."
With deliberate hands, Shirō reached across the table and nudged Riku's massive cake backward — six inches, eight inches — until his own small cake sat front and center before Yoru. The candle flames on the 1 and 9 flickered with the movement, casting tiny orange halos on the tablecloth.
"Okay."
Yoru nodded. The cake was small, but the effort was real. She could see the receipt sticker on the box behind it — he'd paid extra for the strawberries. Something about that simplicity felt honest.
His cake is smaller but at least he's not the one making me want to scream into a pillow right now.
As for the enormous three-tiered monument Riku had brought — she didn't want a single crumb of it. Not from him. Not tonight.
But Madam Hirose had other ideas.
"Let's not waste Riku-kun's cake either." The matriarch was already reaching for the box of long matches on the counter. "We'll light them both. It's the thought that counts, after all."
The match hissed against the striker — a bright sulfur flare — and Madam Hirose touched the flame to each candle atop Riku's cake with the efficiency of a woman who did not believe in unnecessary drama.
Riku-kun went through the trouble. The least we can do is acknowledge it.
The tension curdled.
From her position near the kitchen doorway, Hazuki Uta narrowed her amber eyes. She'd been watching the entire exchange with the quiet intensity of someone reading a mystery novel's final chapter. Her gaze moved from Shirō's rigid posture, to Yoru's flushed face, to the back of Riku's head — and stayed there.
Something's off. This doesn't feel like just a birthday party.
She tucked a strand of chestnut hair behind her ear and said nothing.
---
The arrangement settled itself naturally, the way constellations form — proximity dictating position.
Yoru sat before the two cakes. To her left stood her mother, Madam Hirose, hands clasped in front of her waist. To her right, Shirō, vibrating with barely contained possessive energy.
Riku — blocked from Yoru's side by Shirō's deliberate positioning — had drifted to stand beside Satō Kiyō, who offered him a polite, somewhat apologetic smile. Her brother's behavior tonight was not lost on her.
Uta lingered at the far end, arms crossed loosely, watching.
One by one the candles caught. Twenty-one small flames between the two cakes, their light pooling golden across the tablecloth and Yoru's hands.
Shirō jogged to the wall switch.
Click.
Darkness swallowed the room.
The only light left was candlelight — warm, amber, trembling — painting Yoru's face in soft strokes. The shadows carved her cheekbones sharper, turned her dark hair into ink, made the gloss on her lower lip gleam like wet glass. She looked, in that flickering half-dark, like a painting someone had prayed into existence.
"Yoru, make your wish and blow!"
She nodded.
"Nn~..."
The sound slipped out softer than she'd intended — honeyed, breathy, the kind of sound that belonged behind a closed bedroom door. Shirō blinked in the darkness, a warm current rolling through his stomach.
Her voice... she sounds so cute tonight. So soft.
His mind drifted — to the promise she'd made. Tonight, after the party, after everyone left. Their first time. He'd been thinking about it for weeks, rehearsing it in his head like stage directions. The thought alone was enough to strain the front of his slacks, a visible tent forming in the dark that he instinctively covered with his hand.
Yoru pressed her palms together. Closed her eyes. The candlelight danced behind her eyelids—
And inside Riku's pocket, his thumb found the dial.
He skipped third gear entirely.
Straight to four.
Bzzzzzzzz—
The vibrator roared to life. Not the gentle, teasing pulse of before — this was a deep, aggressive throb that slammed against her clit with mechanical fury, the frequency so high it blurred into a single, unbroken wave of sensation that radiated from her core outward through her thighs, her stomach, the base of her spine.
"Nn—... ahh...?"
Her prayer shattered.
The moan escaped before she could cage it — a short, bitten-off sound, half gasp and half whimper, swallowed immediately by the clamp of her teeth against her lower lip. Her eyes flew open. The candle flames blurred. Her inner walls clenched involuntarily around nothing, and a fresh flood of slick heat pulsed out of her, soaking through her panties and pooling against the wood of the bench beneath her.
No no no no no—
She lunged forward and blew.
Hard. Desperate. Not a gentle birthday wish but a panicked gust that extinguished every candle at once — both cakes, all twenty-one flames, snuffed in a single violent breath. Thin ribbons of smoke curled upward, carrying the scent of burned paraffin into the absolute darkness.
Total black.
Yoru's left hand shot out and fisted the tablecloth, knuckles white, tendons standing out like bridge cables. Her right hand clamped over her mouth — fingers pressing hard enough to leave marks. Her body shook. Not trembling — shaking, the kind of full-body vibration that rattled her teeth and made the bench creak beneath her.
The vibrator hammered at the fourth setting, relentless, and the wet obscene buzz of it against her soaked flesh was audible if you stood close enough — a faint, rhythmic nnnnn buried under the ambient noise of the room. Her clit throbbed like a second heartbeat, swollen and oversensitized, each pulse of the toy dragging her closer to an edge she absolutely, categorically could not fall over. Not here. Not with her mother three feet to her left.
Shirō is right there. Mom is right there. If I make a single sound—
She bit into the meat of her palm. Hard.
"Slo—...!"
The word tore out of her — a strangled, half-formed plea that cracked in the middle.
"What's wrong? Yoru?"
Shirō's voice, concerned and immediate, came from her right. She felt him shift closer in the dark — heard the rustle of his shirt, felt the displaced air as his hands reached for her shoulders.
"Let me—"
His fingers were inches from her body.
Yoru's face burned so hot she could feel her own pulse in her cheeks, her ears, the bridge of her nose. Between her legs, the vibrator buzzed against flesh so wet it had lost all friction, the toy skating across the slick surface of her folds in small, maddening circles driven by the involuntary clenching of her inner muscles. Her nipples were hard beneath her blouse — two sharp points visible to no one in the dark, aching, untouched.
She shoved Shirō's hands away.
Both palms flat against his chest — push.
If he touched her now — if he felt the tremor in her body, the heat radiating off her skin, the damp on the bench — the party was over. Her birthday would become the worst night of her life.
"Wh— what?"
Shirō stumbled back half a step, hands hanging uselessly in the dark.
She pushed me? Why would she push me?
A soft click echoed from the far wall.
Light flooded the room.
Riku stood by the switch, one hand still resting on the panel, the other sliding casually out of his jacket pocket. In the same fluid motion — invisible to everyone — his thumb pressed the stop button.
The buzzing died.
Silence.
Yoru collapsed forward onto the table, her cheek pressing against the cool white cloth, arms splayed on either side of the nearest cake. Her chest heaved — sharp, ragged breaths drawn through parted lips, each exhale fogging against the tablecloth. The sudden absence of stimulation felt almost as violent as its presence, leaving her clit pulsing with phantom vibrations, her inner thighs trembling, the soaked fabric of her panties cooling against oversensitive skin.
She sucked in air like a drowning girl pulled to shore. Greedy, shaking gulps.
It stopped. Thank god. Thank god it stopped.
The room's light was merciless — exposing the deep flush across her face and neck, the faint sheen of perspiration along her collarbone, the unsteady way she pushed herself upright. She smoothed her expression with visible effort, assembling the mask of normalcy piece by piece, the way you'd rebuild a house of cards in a windstorm.
"Are you sick? If you're feeling unwell, you should say something."
Riku's voice arrived from behind her — close, warm, carrying a tone of genuine concern that would have fooled a polygraph. He'd crossed the room without sound, and now stood at her back. She could smell his cologne — something dark and woody, sandalwood layered over black pepper — and feel the heat of him through the thin fabric of her blouse.
Her heart hammered. Thud-thud-thud-thud—
"Is there anything I can do for you?"
His hands settled on her shoulders. Broad palms, steady fingers, a touch that was gentle on the surface and devastating underneath. His thumbs rested against the junction of her neck and trapezius, and the warmth of his skin bled through the fabric directly into her overwired nervous system.
He leaned slightly forward.
She couldn't see his face, but she could feel it — the angle of his breath against the crown of her head. And reflected faintly in the polished surface of the cake knife on the table, she caught the ghost of his expression.
He was smiling.
The kind of smile a devil wore when offering you exactly what you wanted at a price you couldn't afford.
I'm going to kill him. After this party I am going to actually, literally—
Shirō's hand closed around Riku's wrist and wrenched it off Yoru's shoulder.
"Can you back off?" Shirō's voice had dropped — low, tight, stripped of all politeness. His grip on Riku's wrist was white-knuckled. "I don't know why you're even here, but you are NOT welcome. Not tonight."
The room went still.
"Shirō!"
Yoru's voice cracked through the silence — sharp, displeased, a whip-snap of disapproval that made Shirō flinch as if he'd been slapped.
The rebuke landed harder than any physical blow could have. Something fractured behind Shirō's eyes.
"You're MY girlfriend." His voice shook. "Why does HE get to— why is he—"
"Shirō!"
Kiyō stepped forward, one hand raised, her brow creased with secondhand mortification. Her brother was spiraling — she could see it in the rigid set of his shoulders, the wild look in his eyes. This was a birthday party, not a courtroom.
Little brother, please. Read the room for once in your life.
Near the kitchen entrance, Madam Hirose watched the scene unfold with an expression that had cooled several degrees. The warmth she'd initially extended to this Satō boy — polite enough, earnest enough, the kind of young man who brings a small cake and means it — was evaporating like morning frost under noon sun. Possessiveness was not a quality she admired. Jealousy even less so.
Perhaps I misjudged this one.
She said nothing. She didn't need to. The silence of a disapproving mother filled a room more thoroughly than any words could.