Dusk had nearly settled by the time MizunoAiri arrived at the Kizaki family home.
The sky was golden, and the evening air carried the scent of camellias from the small garden by the fence.
The house was modest but neat, two stories tall, its white paint reflecting the last light of the sun.
She stood a moment at the door, smoothing her travel-tousled hair.
The cream knit dress she wore felt soft against her skin, and her white stockings glowed under the warm porch lamp.
I can do this… it's just studying, she told herself.
The door opened softly.
A gentle-faced woman, Kizaki Naomi, smiled from inside.
"Oh, you must be Mizuno Airi? Kiryuu said you'd be coming."
"Y-yes, thank you for having me, ma'am."
"Come in. He's upstairs, but stop for tea first. Rinka, call your brother."
Light footsteps approached.
A short-haired black-haired girl appeared, mischievous grin in place — Kizaki Rinka, Kiryuu's younger sister.
"He just showered, I'll go get him!" she sang, sprinting for the stairs and shouting, "Onii-chan! Your girl guest is here!"
Naomi chuckled; Airi could only smile nervously.
The living room was warm — family photos on the walls, a small bookcase, the smell of green tea and sweet bread filling the air.
A few minutes later, Kiryuu came down the stairs.
Black tank top, athletic shorts, hair still damp.
He rubbed his neck with a towel, voice even:
"You're early. I figured after dinner."
"You said we could start this evening," Airi replied, eyes flicking aside, trying not to stare.
Naomi raised a knowing brow with a faint smile.
"Then study in Kiryuu's room. Don't forget dinner later."
"Yes, ma'am," they answered almost at once.
The staircase to the second floor was narrow and softly carpeted.
Following behind, each step felt heavier than the last.
When Kiryuu opened his door, the scent of soap and coffee greeted her.
The room mirrored its owner: part man, part mind.
Anime posters on the wall; shelves stacked with novels, manga, and piles of summer training notes.
In the corner, a small whiteboard crammed with calorie counts and workout lists.
Kiryuu cleared a few books off the low table.
"Sorry for the mess. Sit here."
Airi folded onto a round floor cushion, setting her laptop and notebook down.
Kiryuu cracked the window; evening air drifted in, orange light washing the room like an old film.
"You really want to study this late?"
"Yes," Airi said softly. "If I keep waiting, nothing changes. I want to know how you think — how you answered those questions."
Kiryuu smiled faintly and sat across from her.
"Alright. Let's see how far you can catch up."
The fan spun lazily as pages opened.
Their first study session began — two students bringing different intentions into the same room.
The air here felt different from the living room — soap, paper, and a faint, masculine trace.
Sunset bled through the curtain, drawing long shadows on the floor.
Airi sat cross-legged, laptop and books on the low table.
The small desk fan hummed; the only other sound was her own heartbeat.
Across from her, Kiryuu adjusted a charging cable, shoulders tensing slightly as he leaned over.
The black tank outlined the clean lines of shoulders and arms shaped by a summer's work.
Airi pretended to fuss with a book, but her eyes strayed to his reflection in the laptop screen.
He really is different now… not just in looks.
Kiryuu straightened and faced her.
He picked up an old notebook, flipping through dense handwriting.
"These are my summer notes," he said quietly. "Not schoolwork — focus. How I forced myself to understand new things."
He handed it to Airi.
Neat, orderly script — logic outlines, mind maps, formulas explained in his own words.
"You… made all this yourself?"
"No one else was going to help then."
"It reads like a professional guide."
"When your life depends on success, you learn fast."
Airi swallowed. His voice was low but steady; each word slipped straight into her head like instruction.
She opened a blank document.
"Okay. Teach me how you think when you see a question."
Kiryuu nodded, leaning in.
Now only a handspan apart, she could see his eyes reflected in the glass.
He began sketching on paper, voice slow, guiding.
"Look for patterns. Every question has a trap, and our brains are trained to follow the same path. I change the route."
"Meaning?"
"If everyone answers the same way, the extraordinary answer comes from the one who looks another way."
He paused, watching her.
"Like now. You want to learn — and you came straight to my house. That's not a normal student move."
Airi smiled small and lowered her gaze.
"Maybe I just want quick results."
"Or maybe you're looking for something else."
She didn't answer.
The hush between them held — fan and tiny desk clock marking time.
Kiryuu leaned back, noticing the room as if anew —
Posters, old manga, a few magazines left half stored: leftovers of an ordinary boy's life intersecting with a mind from somewhere harsher.
"This room… is kind of messy," he said. "I forgot you were coming."
"It's fine," Airi replied quickly. "I like rooms with character. You… look like you really live here."
She glanced at the shelves packed with books and training sheets.
"It's all exercise, discipline, stats…"
"I had to change everything."
"And you did."
Kiryuu shrugged.
"The body's easy to change. Mindset is hard."
Airi smiled slowly. "But you changed both."
Minutes later, they were writing again.
Kiryuu explained logic with quiet patience — voice low enough that each word felt close to her ear.
Airi copied diligently, though every time her hand brushed the shadow of his on the tabletop, her focus skipped.
Why do I feel like this… it's just studying, right?
Kiryuu paused, studying her.
"You okay?"
"Y-yeah. Just a little dizzy."
"No need to force it. We can rest."
"No. Keep going."
He huffed a laugh. "Stubborn."
"If I wasn't, I wouldn't have come to your house."
Kiryuu shook his head, a thin smile.
"Alright. But don't forget to breathe."
Evening tipped into night.
The desk lamp threw a soft halo over their faces.
Airi watched his profile — the set of his jaw, the quick flick of his eyes between book and board.
She tried to rewrite a formula, but only his earlier words remained:
"If everyone follows the same path, I change the route."
And for some reason, she wondered what would happen if she changed hers, too.
The desk lamp was the room's only light now.
Crickets replaced birds outside; a night breeze lifted the thin curtain.
The air felt quiet — expectant.
Kiryuu slid a workbook toward her.
"Let's try mid-level logic. Solve this without the example."
He wrote lines on a small board, fast and clean.
Airi bent over it, but her eyes kept drifting to his hands — the way his fingers moved, the way his shoulders squared when he explained.
She wrote slowly, thinking.
Kiryuu waited in silence — not judging, making sure she understood.
"I… think it's this," Airi said softly, pointing to the last line.
Kiryuu leaned in, looking over her shoulder.
She could feel his breath ghost her cheek.
He tapped the middle of the page, voice still low.
"You're close. But you took the path everyone takes. Go back to step two — change direction. Switch perspective, and the final result shifts."
Airi looked again, then nodded.
"So, don't follow someone else's route."
"Right. Academic problems are like life. Sometimes you have to be wrong once to learn the right way."
She smiled a little. "You talk like a philosopher."
"My job's to think people into headaches."
They laughed, and for the first time since she'd arrived, the tension eased.
A moment later, Kiryuu leaned against the wall, arms folded.
Airi kept writing, brow furrowed.
She was calmer now; each time he coached, she repeated until it stuck.
"You learn fast," Kiryuu said at last.
"Or maybe my teacher's good," Airi answered without looking up.
"I only point the way. You choose the steps."
"Like you said — change my own route?"
"Yeah."
Their voices were quiet — a conversation careful not to disturb the night.
A draft slipped through the window.
A loose strand of Airi's hair brushed Kiryuu's arm as she bent toward the table.
She flinched and straightened.
"Sorry—"
"It's fine," he replied quickly. "Keep going."
But from then on, her focus wavered.
She kept writing, yet her thoughts circled the closeness, the calm of his voice.
He only wants to help me study. I'm the one overthinking.
So why does it feel like…
She drew a long breath.
"Do you tutor people like this often?"
"Not many ask."
"Hanabira-sensei too?"
Kiryuu paused.
"She asked for help; I gave it. This time, I'm actually teaching."
Airi lowered her gaze, a small smile.
"If I work hard, do I get a reward too?"
"Your reward is moving up the ranks. That's it."
She laughed softly. "You're… not great at jokes, are you?"
"I'm serious when someone asks for help. I offer choices, not price tags."
Airi fell quiet.
His words echoed again:
Offer choices, not price.
Hours slid by in an odd hush.
Kiryuu read from his laptop; Airi copied and asked questions; time stretched thin.
Sometimes their eyes met — quick, but enough to stir something in both.
Downstairs, Rinka's voice drifted up, calling them for dinner.
Kiryuu glanced at the door, then back to Airi.
"Break?"
"Sure…"
"Want to eat?"
"Later. I want to finish this."
He nodded, stood to fetch water.
When he turned back, Airi was watching him — not with a student's gaze, but something harder to name.
And in that quiet instant, without either noticing, their first lesson shifted course —
from logic to something far more personal.
The clock neared nine.
The room was half-dim — only the desk lamp lit the books and the faces of two people still writing.
Airi stretched, easing her shoulders.
Across from her, Kiryuu wrote notes, body leaning slightly forward.
Her sweater dress felt warm beneath the light; the air grew quieter.
"Water?" Kiryuu asked, standing.
"Please."
He set the bottle before her.
As she twisted the cap, her hand slipped — water spilled across the table, running toward where Kiryuu stood.
"Ah! I'm sorry! I'm sorry!"
"It's fine, I'll—"
"It's alright, you don't need—"
But Airi was already moving.
She grabbed paper towels, leaned in to blot the spreading puddle.
In her haste, her hand brushed the damp patch on Kiryuu's pants as well.
Kiryuu froze — half scolding, half startled.
"Airi—"
"I'm sorry! I was just—"
But Airi didn't move.
Head bowed, hair falling over her face, her breath uneven.
"I just… wanted to help."
Her hand stopped there, and time seemed to catch.
Both went silent; only the small clock kept ticking.
The cool air felt different now — denser, heavier, as if something else filled the space.
Kiryuu watched her for a long moment, saying nothing.
His face remained composed, but his eyes changed — not anger, not confusion, but the awareness that they'd drifted past a line best left intact.
Airi lifted her head — and the room fell perfectly still.
"Shit, I'm so sorry!" Airi gasped, knocking over her water glass. Ice cubes skittered across Kiryuu's desk, soaking his physics notes. "Let me clean this up."
She dropped to her knees, grabbing tissues with shaky hands. The pale beige fabric of her sweater dress stretched tight across her thighs as she leaned forward. Her fingers brushed the wet spot darkening his black shorts.
Kiryuu froze. Her knuckles grazed the growing hardness beneath the thin fabric. She didn't pull away. Her breath hitched, warm against his thigh.
"I only wanted to help," she whispered, looking up through fallen strands of hair. Her palm pressed flat against him, feeling his cock pulse and swell under her touch.
The clock's ticking filled the silence.
Kiryuu hauled her up by her arms, his mouth crashing onto hers. Her gasp melted into a moan as his tongue slid against hers, tasting faintly of mint.
His hands slid under her sweater dress, bunching the knit fabric at her waist. The lace-trimmed stockings slipped down her thighs as he yanked her closer.
He guided her back to her knees, fingers tangling in her hair.
Airi peeled his shorts down, freeing his thick, 17cm cock, and freezed when looked at that.Giggles.
She licked a slow stripe up the underside before taking him deep, her lips stretched tight.
Kiryuu groaned, thrusting shallowly as her throat fluttered around him.
Suddenly,
he pulled her onto the bed, her sweater dress riding up to her hips.
Kiryuu ripped her stockings aside, fingers plunging into her soaked pink pussy. Airi cried out, "ahhhhh...",arching off the mattress as he sucked her clit, his tongue flicking hard until her thighs trembled and her climax hit with a sharp,
" Kir... yuuuuu.... ",
gasping moan.
Clothes vanished—
Kiryuu tearing off his singlet, Airi wriggling free of her dress.
Naked now, he settled between her legs, her hand guiding his swollen cock against her dripping entrance.
Kiryuu rubbed the slick head over her swollen lips, the friction drawing another shuddering orgasm from her before she wrapped her legs around his waist. He pushed inside with one deep thrust.
Her tight heat clenched around him as he moved—
slow, grinding strokes that stole her breath.
Airi's nails raked down his back, her moans sharpening with each deep push.
Her breathed faster.
Sweat slicked their skin where their bodies met, the wet slap of his hips against her thighs echoing in the quiet room.
She trembled, crying out as another climax ripped through her, her pussy drenching his cock.
Kiryuu pulled out abruptly, flipping her onto her knees. He gripped her hips, driving back into her with brutal force.
Airi gasped, arching her back as he pounded deeper, each thrust jolting her forward.
"Fuck, you take it so good," he growled, his fingers digging bruises into her flesh. Her choked whimpers mixed with the filthy sound of his cock plunging into her soaked cunt.
Without breaking rhythm, he rolled them sideways into a spoon, his chest pressed to her back.
His hand cupped her breast, pinching her nipple as his cock stayed buried inside her.
"Cum again," he demanded, thrusting shallow and fast.
Airi obeyed, shuddering against him with a broken sob, her ass grinding against his hips.
His release hit hard—
a guttural groan as he emptied himself deep into her womb. Airi felt the hot pulse of his cum flooding her, her own body convulsing in response.
They lay tangled, his softening cock still nestled inside her, her satisfied smile pressed into the pillow as their ragged breathing slowed.
The lamp caught in her eyes.
Everything after that went undescribed — only that the night passed in a warmth no words tried to capture.
Some time later, quiet returned — steady, measured breath.
The desk lamp still burned; books lay open; the curtain breathed with the night wind.
Airi had fallen asleep by the table, her head resting on Kiryuu's shoulder.
A thin blanket covered her — who had placed it, no one said.
Kiryuu sat silent, gazing out the window; his face unreadable — like someone who knew a boundary had been crossed, and chose not to speak of it.
Humans are strange, he thought.
Given a lesson, they look for a feeling.
He glanced down at Airi's sleeping face and drew a slow breath.
"Lesson's over," he whispered.
Morning crept through the half-open curtain.
Soft white light touched the wooden floor, climbed the cluttered desk — books, pencils, a cream sweater folded halfway.
The room was hushed save for birds outside the window.
Airi's eyes fluttered open.
The ceiling of Kiryuu's room came into focus — and then other things:
the warmth along her body, the light blanket drawn from chest to feet, and a subtle rhythm beside her that wasn't her own.
She turned.
Kiryuu was still there, half seated at the bedside, his head tipped against the wall.
The blanket wrapped both their waists, covering more than was explained.
His skin caught the morning light; his face was calm — not regretful, not making excuses.
Airi clutched the blanket and lowered her gaze.
Her body felt tired — a strain she'd never known — somewhere between ache and… contentment.
She lifted her eyes, studying his profile.
"You really are… something else," she whispered.
Kiryuu stirred, halfway between sleep and waking.
Their eyes met — not teacher and pupil, not strangers, but something unnamed in between.
"You're up early," he said quietly.
"I was afraid this was just a dream."
"And if it is?"
"I don't mind… if all dreams are like this."
A small smile formed — relieved and confused at once.
Kiryuu didn't return it; he only drew the blanket higher over her shoulder, shielding more from the world.
"You should rest more. Today will be long."
Airi nodded, though her gaze lingered on him.
In her heart, no words could quite hold what pressed at her chest —
a tangle of awe, a little fear, and… something like a craving.
She lay back, letting the morning light ring them both.
Kiryuu looked out the window while Airi's eyes eased closed again, the faint smile still on her lips.
And in the quiet space between two still hearts, a new secret began to grow.
———————————————————
💜 Character Profile — Mizuno Airi (水野 愛理)
Year / Section: Year 1 – F (International Academy)
Age: 18
Origin: Japan (maternal European heritage)
Role in story: First woman to open Kiryuu's "hidden door"; the initial spark that shifts the academy's social and emotional gravity.
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🪞 Visual / Appearance
Hair: Glossy deep purple that fades to soft lavender at the ends. Waist-length; usually tied loosely with a thick side-braid on the right.
Eyes: Bright violet — large, gentle, and curious; a look balanced between innocent and sly.
Skin: Fair and smooth; warm blush rises on her cheeks when she's flustered.
Build / Height: Balanced, toned curves; ~168 cm.
Style
On campus: Fitted white shirt, short navy skirt, thigh-high white lace stockings.
Off-campus / winter: Cream knit turtleneck dress, paired with minimal gold jewelry (subtle but elegant).
Overall Aura: Sweet but daring — a girl who turns shyness into a desire to understand… and maybe to claim.
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💬 Personality
Outward: Cheery, studious, easy to befriend — yet quietly drawn to adult matters and boundaries.
Inward: Highly impressionable when curiosity is triggered; once invested, she dives all the way down.
Motivation: Prove she isn't a "bottom-rank" student forever; climb on her own merit — yet she's increasingly captivated by Kiryuu in a way that blurs mentor and man.
Symbolism: The First Spark — her choice ignites chains of sensual tension, emotional stakes, and reputation wars around Kiryuu.
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🔧 Competencies & Habits
Learning style: Pattern-seeker; improves drastically with structured prompts and route-shifting logic (responds well to Kiryuu's "change the path" method).
Meta-sense: Listener/observer from the edges (e.g., overhears from outside counseling room).
Masking: Hides strong feelings behind a soft smile.
Time affinity: Dusk, same as Kiryuu — she tends to appear when the sun is about to drop.
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📈 Arc Hooks (Spoiler-safe)
Academic rise: Formerly below #110, jumps sharply after the "study session," drawing attention (and envy) across sections.
Emotional conflict: Tug-of-war between ambition and desire; she wants Kiryuu's mind … and increasingly, the man.
Social ripple: Her proximity to Kiryuu becomes the first public fracture in the academy's hierarchy (and a magnet for gossip, rivals, and tests).
Decision theme: "You have to decide the price" lingers as her personal refrains — what will she offer for the results she craves?
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🎭 Relationship Dynamics (early stage)
Kiryuu Kizaki: Catalyst, mentor, temptation. Airi mirrors his dusk-timing, starts adopting his "re-route" logic, and becomes the first to sense the danger—and still step closer.
Miss Hanabira: Admiration mixed with uneasy curiosity; Airi can't ignore what she suspects and what it awakens in her.
---
🧩 Tells & Micro-Gestures
Twists the loose end of her side-braid when thinking hard.
Smile softens first, eyes sharpen second — the reverse when she's hiding something.
Pauses half a breath before asking intimate questions; resumes in a lower voice.
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🎨 Palette & Aesthetic
Colors: Deep violet, lavender fade, cream, gold accents.
Lighting: Warm dusk tones; lamplight on skin; window silhouettes.
Textures: Knit softness vs. crisp campus cotton — innocence meeting resolve.
---
🗣 Sample Lines (voice reference)
"If everyone follows the same path… maybe I should change mine."
"I want your method — and the reason behind it."
"If there's a price… I'll decide it."