I woke to the sound of my phone vibrating across the bedside table.

A bank notification.

₩13,700,000.

Roughly ten thousand U.S. dollars. I sat up, rubbing the sleep from my eyes.

"Aish..."

The kid was serious.

I opened my email, and there it was: a folder titled Kim Min-jae Case. I started reading. His passport scan confirmed he had indeed turned eighteen, and he was currently studying at a university in California. The rest of the folder, however, was dedicated entirely to one man.

Lee Hyun-woo.

Age: Twenty-eight.

Occupation: Mathematics teacher.

He was formerly employed at Seoul Science High School, one of Korea's top academies for gifted students. He had started teaching there at twenty-five, a rising star in the academic world. Then, three years later, everything changed.

Kim Min-jae, then sixteen, accused Lee of touching him inappropriately. Mr. Lee denied it entirely. Instead, he claimed Min-jae had offered him money in exchange for the final mathematics exam answers. When he refused, Lee alleged that Min-jae hacked into the school's server to steal them.

An internal investigation followed, but the school never released the full findings. In the end, Mr. Lee was cleared, while Min-jae was withdrawn from classes and quietly shipped overseas by his parents. Three months later, Mr. Lee resigned anyway. He now taught mathematics at a small, rural high school in Pyeongchang County, Gangwon Province—as far away from the spotlight of Seoul as he could get.

I opened the attached photographs.

The first showed him accepting a 'Best Mathematics Teacher' award. He looked embarrassed, holding the plaque, scratching the back of his neck as his fellow teachers applauded. The second was taken on a sports field. Vertical lines of middle-school students crowded around him, laughing as they held up a football trophy. Mr. Lee was smiling so brightly his eyes almost disappeared. 

The third photo was a newspaper clipping: 

HIGH SCHOOL TEACHER CLEARED IN SEXUAL MISCONDUCT CASE.

He looked utterly exhausted as he left the courthouse.

The last photo held my attention the longest.

He was sitting alone on a park bench beneath blooming cherry trees, a paperback novel resting in his hands. One leg was crossed neatly over the other. His copper-brown curls looked soft enough to disappear between your fingers, and his round glasses rested low on his nose. His face was small, youthful, with round cheeks and a tiny mole just beneath his left eye. He wore a blue checkered short-sleeved shirt tucked into beige trousers, capped off with brown loafers polished until they shone.

His arms were slim, his shoulders narrow. He looked... cute. Not handsome, exactly. Just cute. The kind of face old ladies would feed extra kimchi to. The kind of teacher parents trusted without question.

Harmless.

Then again, most predators looked harmless.

I closed the folder, pulled up a digital contract, and signed it before emailing it back to my newest client. The only real downside to the job was leaving Seoul. Still, fresh mountain air sounded better than another month staring at my apartment walls.

Two weeks later, my new identity was complete. I was no longer Detective Han Do-yun. I was now:

Kang Ji-ho.

Seventeen years old.

Final-year high school student.

According to my new background file, I was a troubled kid who had transferred so many times that no prestigious school wanted him anymore. To smooth things over, my fake parents had donated a generous amount to the rural school's library. Money opens doors, even in the countryside. Especially in the countryside. The file stated my parents traveled overseas constantly for work, meaning I lived completely alone. No questions asked.

The apartment I'd rented sat on a quiet hillside. Two bedrooms, simple furniture, spotless floors. The living room overlooked rolling green mountains, and the nearest convenience store was a fifteen-minute ride away by bicycle. There was nothing out here but forests, rice fields, and winding roads. The school bus only passed twice a day, so my bike from Seoul arrived the very same afternoon. Perfect.

The next morning, I started surveillance.

Mr. Lee lived in an old, three-story apartment building. Room 203. One bedroom, one goldfish, no girlfriend, no roommate, and absolutely no suspicious visitors. At seven-thirty sharp, he locked his door and hurried toward the bus stop, balancing a travel mug of coffee in one hand and a piece of toast in the other.

"Aish..."

He’d overslept. Again.

When the bus arrived, he bowed politely to the driver. "Annyeonghaseyo." He greeted the school security guard with another respectful nod upon arrival. As soon as he walked through the gates, a group of students ran toward him.

"Seonsaengnim!"

He stopped in his tracks to fix one girl's crooked necktie. Noticeably, another student's backpack zipper was gaping open; Lee quietly zipped it up for him without saying a word. His smile reached his eyes.

Something twisted uncomfortably in my stomach. I ignored it. Tomorrow would be my first day of school, and my plan was simple: become the school's biggest headache. Break rules, talk back, and get myself sent to Mr. Lee's office over and over again. People always slipped up in private.

The next morning, I arrived ten minutes late on purpose. My uniform was almost perfect—almost. A crisp white shirt, grey trousers, and a striped tie hanging loose around my neck with the top button undone. My black hair was bone-straight, the side fringe falling just above my eyes. The back brushed the nape of my neck, measuring just a little longer than most strict schools allowed. I'd tucked a strand behind one ear, but the look still made me look more like a rebellious idol than a transfer student.

I looked exactly like a rich chaebol heir who had never heard the word "no" in his entire life.

As I entered the classroom, every conversation ground to a sudden halt. Girls stared open-mouthed, while the boys immediately began sizing me up. At the back of the room, one student had another in a tight headlock while their friends laughed. Bullies. Noted.

Through the open windows, I caught the faint smell of fertilizer drifting in from the nearby fields. Definitely not Seoul.

Seeing an empty seat waiting in the back row, I walked over, dropped my backpack onto the desk, and slouched heavily into the chair. Phone out, head down. I ignored everyone completely, waiting out the whispers that inevitably started up again.

Ten minutes later, the classroom door slid open.

Mr. Lee hurried inside carrying a precarious stack of textbooks and loose sheets against his chest.

"S-sorry, everyone," he said breathlessly, using the back of his wrist to push his round glasses back up his nose. "The copier jammed again."

The class burst into familiar laughter, clearly used to his chronic unpunctuality.

Only then did I get my first proper look at him.

And froze.

The photographs in his file hadn't done him justice. Not even close.

The man standing in front of me looked... different. Softer. Warmer. His copper-brown curls were slightly messy, as if he'd repeatedly run his fingers through them on his way up the stairs. Morning sunlight streamed through the tall windows behind him, catching the loose strands and turning them almost golden.

His face was strikingly youthful—far too youthful for a twenty-eight-year-old high school teacher. His cheeks were flushed pink from hurrying to class, giving him an almost boyish appearance. The tiny mole beneath his left eye stood out prominently in person, drawing attention to warm eyes that curved into gentle crescents whenever he smiled.

And he was smiling now. A real smile. The disarming kind that reached all the way to his eyes, crinkling the corners.

For a brief, ridiculous moment, I actually understood why the students adored him.

"Cute," someone whispered in the front row.

Cute. That was exactly the problem. He didn't look anything like the predator I'd built up in my head. There was no calculating gaze. No cold, predatory charm. No carefully crafted, intimidating persona. Just a slightly flustered, endearing teacher apologizing to a room full of teenagers for being late.

I found myself staring, unable to tear my eyes away. The blurry surveillance pictures had suggested he was attractive, but the real thing was... considerably worse. Or better. Depending on how one looked at it.

Aish.

I quickly schooled my expression, hardening my features back into a mask of total indifference. Attractive people could still be monsters. I'd learned that lesson the hard way over my years on the force.

Cheating husbands with movie-star smiles. Violent men who looked like perfect, doting fathers. Disgruntled employees with gentle faces and impeccable manners. Vindictive exes who could cry on command and play the victim to perfection.

Attractiveness meant absolutely nothing when it came to crime. Monsters rarely looked like monsters. Most looked completely ordinary. Some looked kind. A few looked so disarmingly beautiful that people ignored every screaming red flag until it was far too late.

Mr. Lee finally cleared his throat and tapped his knuckles lightly against the wooden podium. "Everyone, settle down, please."

His voice was soft, but carried a steady, natural authority. Gentle. Patient.

The classroom chatter quieted almost immediately.

Interesting. They respected him without him ever needing to raise his voice.

"We have a new transfer student joining us today," he announced. His eyes moved toward the back of the room and landed directly on me.

For a fraction of a second, his expression went entirely blank—almost as if he hadn't expected me to look the way I did, either.

"Kang Ji-ho?" There was the slightest hesitation in his voice as he read my name off his roster. "Would you come up and introduce yourself?"

I stood up slowly, shoving my hands deep into my uniform pockets and taking my sweet time as I sauntered down the aisle.

As I made my way to the front, I caught him studying me, his gaze trailing over my deliberate posture. He quickly averted his eyes the moment our gazes met, a nervous flicker passing over his features.

Nervous. Not fearful, and not suspicious. Just... apprehensive.

He'd obviously read my file. The repeated transfers, the extensive disciplinary records, the absent parents. To him, I wasn't just a new face in class—I was a walking headache he'd already been warned about by administration.

When I finally turned to face the room, thirty pairs of eyes watched my every move.

"I'm Kang Ji-ho."

Dead silence filled the room.

"I got kicked out of Seoul, so here I am."

Without another word, I made to head straight back to my seat.

"Ah... one moment," Mr. Lee said quickly, offering an awkward, polite smile to smooth over the sudden drop in temperature. "Could you tell everyone which school you transferred from?"

I rolled my eyes, letting the entire room see my annoyance. "It's in my file."

Gasps rippled through the classroom. Mr. Lee blinked, momentarily taken aback by the blunt disrespect.

"I know," he replied smoothly, maintaining his patient smile despite the tension. "But your classmates might like to hear it from you."

"Han Academy, Seoul," I said, watching the stunned expressions spread across the room. I looked directly into Mr. Lee's eyes, my voice dropping an octave. "You read my file, right?"

Murmurs immediately exploded across the desks. Not only was Han Academy the premier elite private school in Seoul, but my outright hostility toward a teacher was unheard of in a quiet town like this.

A few students stared at me in absolute disbelief. Someone near the window muttered under their breath, "Ya... he's totally crazy."

Perfect.

Mr. Lee opened his mouth to address my attitude, then closed it just as quickly, choosing his battles wisely. Our eyes locked for a tense second before he pulled his away, turning back to address the whispers in the room.

"Well..." He chuckled softly, brushing off the thick atmosphere with practiced ease as I sauntered back to my desk. "Let's all do our best to help Ji-ho settle in. Today, we're starting algebra."

The class groaned in collective agony. "Neeee, seonsaengnim..."

Mr. Lee smiled warmly. "I know, I know..." he said jovially, turning to the whiteboard to begin writing out the first set of equations.

For the next hour, I didn't look at the board once. Instead, I spent the lesson alternating between analyzing his teaching style and blatantly scrolling through my phone under my desk.

His method was fascinating. He knew every single student's name and learning pace. He praised good answers enthusiastically and never embarrassed anyone who struggled with a problem. The students weren't afraid of him; they genuinely liked him. Maybe they even loved him.

"Kang."

I looked up. Mr. Lee was watching me from the front of the room, his eyes kind and bright behind his round frames.

"No phones during class, please," he said. His tone stayed perfectly calm. There was no rising anger in his voice, no heavy threat of detention—just a quiet, steady reminder.

I locked the screen slowly, before sliding the device into my pocket.

Mr. Lee gave me a single, approving nod before returning to his lecture.

Twenty minutes later, he began walking up and down the aisles between the desks, checking everyone's progress. I hadn't written down a single number. Naturally, my entire strategy depended on provoking him, getting noticed, and forcing him to call me into private spaces for discipline.

When he reached my desk, he paused, looking down at my blank notebook.

"Not taking notes?" he asked softly.

"No."

A few nearby students turned around, looking utterly horrified on my behalf.

Mr. Lee merely sighed, a gentle release of air. Then his gaze dropped to my hands resting idly on the dark wood of the desk. His eyes lingered on my fingers for a beat too long.

"You play basketball?"

I frowned slightly before answering, "Yeah?"

"Position?"

"Shooting guard."

His expression shifted for a split second, registering a sudden flicker of surprise—maybe even nostalgia—before he carefully smoothed it away.

"How'd you know I played seonsaengnim?"

"You have calluses here," he noted softly,  pointing a finger toward the base of my palm without actually touching me.

I stared up at him. Most people couldn't tell a basketball player from a soccer player just by looking at the wear on their hands.

He straightened his posture, adjusting his glasses on the bridge of his nose. "My younger brother used to play."

A lie. 

I knew every single detail in his background file. Lee Hyun-woo was an only child.

Our eyes met again; this time his polite smile looked tight, strained at the edges. He turned back toward the front of the classroom, doubling back down the aisle, checking the other students' notes as he went.

I leaned back in my chair, watching his retreating figure.

There was definitely more to this sweet countryside math teacher than met the eye.