[JUX-794] Mischievous teacher Kang Seulgi

The first snow of December falls steadily outside the frosted windows, quieting the world in a blanket of white. The heater hums faintly in the corner, but it’s losing its battle against the cold. Students shuffle into the room slowly, hands buried in their jacket pockets, faces flushed from the biting air. The class feels sleepy and subdued. Except for the back row.

Kang Seulgi enters with her usual composure, the click of her brown heels sharp against the silence. She sets a neat stack of books on the desk, brushing a strand of her orange hair behind her ear before peeling off her coat. Beneath it, she’s dressed with deliberate precision: a silky brown blouse that clings just enough and tight brown leather shorts that cut high on her smooth, bare thighs.

The contrast is striking. Warm layers on everyone else, while she stands there as though immune to the cold. Her round glasses frame her sharp gaze as she finally looks up.

“Good morning."

Seulgi says softly, her voice cutting through the muted hush.

“We’re continuing with evolution today. Open your books to page 54.”

The students comply, the sound of pages turning filling the room. But the boys in the back; Jaehyun, Minho, Jiho, Hyunwoo, and Seungmin; sit still and quiet, their jackets loose, ties undone. Their books remain closed, pens idle. They’ve made no effort to look interested, but Seulgi doesn’t acknowledge them.

She turns her back to the class and begins writing in large, fluid letters on the whiteboard: Natural Selection. Adaptation. Competition.

“In biology,"

She talks, evenly underlining the word Adaptation.

“natural selection determines who thrives and who doesn’t. It isn’t always the strongest who survive. It’s those who know how to adapt.”

Her voice is calm, almost melodic, but the rhythm of her movements is deliberate. She stretches slightly to underline a point, her blouse dipping faintly at the back. The motion feels natural, unremarkable to most. But she knows the back row is watching. She finishes writing and caps the marker with a snap.

“Now, let’s start with a quick recap.”

The minutes tick by slowly as Seulgi explains the core principles of evolution. The heater hums louder, groaning as though in complaint, but the room remains cold. Some students yawn quietly, their pens moving lazily over their notebooks.

Seulgi leans back against the edge of her desk, resting one hand beside her as she crosses her legs slowly at the knee. The motion is smooth, deliberate, and reveals the full length of her bare, toned thighs. The leather of her shorts catches the soft light filtering through the window, dark and sleek against her skin.

Her other hand adjusts the glasses on her nose as she continues.

“The environment decides which traits are an advantage. For instance, animals in cold climates adapt by growing thicker coats or conserving energy.”

A pause.

“In this case,"

She adds, her tone soft but edged.

“you could say survival is about knowing how to endure... or how to stand out.”

The words seem to settle heavily in the air. From the back, Jaehyun shifts faintly in his seat, dragging a boot noisily against the floor before stopping. Minho runs his fingers absently through his hair, though his gaze hasn’t moved from the front of the room. Hyunwoo’s pen is still, the cap flicked on and off in slow rhythm.

Seulgi knows what she's been doing to them for the last couple weeks. But she doesn't even grant the five of them a glance. She focuses instead on a stack of papers, as if oblivious to the tension.

Halfway through the lesson, Seulgi moves to the board again. She uncaps the marker, poised to add another word to her now pretty large collection of keywords: Selection.

The marker slips suddenly from her fingers, tumbling noisily to the floor.

“Oh."

She murmurs softly, pretending to be surprised.

Without hesitation, she bends at the waist to retrieve it. The movement is deliberate yet measured. Her blouse stretching faintly as she leans forward, the hem of her dark leather shorts lifting just enough to reveal the perfect shape of her bare thighs. For a second, just a second, there’s a faint glimpse of lace peeking above the line of her shorts. Black lace. That seems to hug her thighs perfectly underneath her shorts. The shape of her perfect ass makes the experience even more rewarding.

The silence that follows is deafening.

From the back, someone’s chair creaks faintly. Jaehyun sits perfectly still, his eyes fixed firmly on the edge of his desk. Minho stares straight ahead, though the faintest movement in his jaw betrays him. Jiho’s fingers pause mid-tap on his notebook, the rhythm forgotten.

Seulgi straightens slowly, marker in hand, and brushes a strand of hair over her shoulder. Her face remains perfectly neutral, as though nothing happened at all.

“Let’s continue."

She says smoothly, turning back to the board.

Toward the end of class, the lesson turns to competition as a key driver of natural selection.

“Competition isn’t always obvious."

Seulgi explains, sitting on the edge of her desk once again. This time, her posture is looser, more relaxed. One heel dangling lazily from her foot as her legs cross. The motion draws subtle attention to the clean line of her thighs, their smoothness standing out in stark contrast to the winter cold everyone else seems to be hiding from. She taps a finger lightly against the edge of the desk, as though in thought.

“Sometimes, survival depends on subtle advantages. A trait that sets one apart from the rest, even if no one notices it at first.”

She allows the words to hang for a moment, brushing her fingers idly along the hem of her blouse. She only barely moves her collar a little to the side. Just the slightest hint of her tits reveal the lack of a bra.

“Nature rewards the clever, the resilient, and those who can endure.”

From the back row, Jaehyun’s pencil rolls off his desk. He doesn’t pick it up right away. Hyunwoo exhales through his nose, sitting back with an expression carefully blank. Minho slouches lower in his chair, his arms crossed tightly over his chest as he looks out the window.

After an otherwise uneventful rest of the class, the shrill ring of the bell cuts through the stillness, breaking the calm atmosphere in an instant. Students jolt upright, snapping their books shut and packing up quickly. Seulgi uncrosses her legs slowly, sliding off the edge of her desk as she gathers her papers.

“Read pages 54 to 60 for homework. We’ll continue on Monday.”

The class empties slowly, students trudging toward the door. The back row lingers longer, as always. Jaehyun is the last to stand, slinging his bag over one shoulder and pausing just long enough to glance back at the desk. His expression gives nothing away.

When the door finally clicks shut, Seulgi exhales softly. She sets her papers neatly in a folder and picks up the red marker, turning it over in her fingers with a faint smile. They're close to breaking already.

The lunch bell echoes through the school, signaling a rare pocket of freedom for the students. The once-quiet halls turn chaotic as voices bounce off the walls, lockers slam shut, and footsteps patter quickly toward the cafeteria. The winter wind howls faintly outside, making the warmth of the building feel like a reluctant escape from the cold.

In the middle of it all, Seulgi walks with slow, deliberate steps.

Her outfit today is different from last week. Still professional but tailored to perfection. She wears a crisp, white blouse with the sleeves rolled neatly to her elbows. A slim black pinstripe vest hugs her torso, cinched with small silver buckles at her sides. Her short pleated skirt, just daring enough, grazes the tops of her bare thighs, leaving smooth skin visible with every stride. A loose black tie drapes over her blouse, and her tall black boots add a confident edge to the look. Her hair is sleek and straight today, cascading past her shoulders like liquid ink. The glasses perched on her nose frame her face, lending her the illusion of untouchable composure.

The sound of her boots clicks with every step as she makes her way toward the teacher's restroom, moving through the chaos with unbothered grace.

Near the far end of the hallway, the same five boys hang around the lockers like they own the place. Their jackets hang open over their uniforms, ties barely in place, looking perfectly disheveled in a way that only makes them stand out more.

As Seulgi rounds the corner, the sound of her heels cuts through the din of students moving past.