Observed - Lee Kang x F!Reader
You thought he was your brother's friend—he always knew you were his.
CW: MDNI, dark themes, stalking, obsession, choking, non-consensual sexual content, creampie, unprotected sex, degradation, violence
A/N: hyunwook ate his role so bad i had to write abt him in his own fiction
You never liked your brother's friend.
There was always something about Lee Kang that unsettled you, something you couldn't quite name. It wasn't that he was rude or unfriendly. If anything, he was painfully quiet. He rarely spoke unless someone addressed him first, and even then, his answers were short, almost mechanical. Most of the time, his head stayed lowered, as if he were more interested in whatever was on his phone or laptop than the people around him.
Lately, though, your brother had started inviting him over far more often than before. At first, you assumed it was just a phase, another friendship that would fizzle out after a few weeks. Instead, Kang became an increasingly familiar presence in your home. According to your brother, the two had gotten close this year after Kang helped him survive his coding class, a favor your brother never seemed to stop talking about.
You supposed it made sense. Lee Kang fit every stereotype of a coding genius. Quiet, reserved, brilliant in ways that made everyone else look hopelessly behind. Yet beneath his withdrawn demeanor was something you could never ignore. His eyes.
Whenever he looked at someone, it never felt like a casual glance. His gaze lingered just a little too long, sharp enough to make your skin prickle, as though he were silently dissecting every expression and movement before storing it away. He never appeared distracted, not really. Even with his head bowed, you always had the strange feeling that he noticed far more than he let on.
And somehow, every time he stepped into your house, that feeling only grew stronger.
At first, you really did try to like him. You chalked his awkwardness up to shyness. You cracked jokes whenever the room grew too quiet, hoping to ease the tension that seemed to follow him wherever he went. You made an effort to include him in conversations, asking questions that were easy to answer and carrying discussions whenever they threatened to die out. It wasn't as though he was unpleasant, just... difficult to read.
Whenever he replied, his voice was barely above a murmur, flat and unassuming, each word delivered in the same dull cadence. He came across as timid, almost nervous around you.
But his eyes never matched the rest of him.
There was nothing hesitant about the way he looked at you.
While his voice remained soft and his posture reserved, his gaze never wavered. It didn't falter under yours or dart away in embarrassment the way a shy person's usually would. If anything, you were the one who found yourself breaking eye contact first, unsettled by the unwavering intensity behind his expression. It wasn't openly hostile or affectionate, it was simply observing. Too carefully and quietly.
His eyes were the problem.
Even when the two of you were occupied with entirely different things, you'd catch the unmistakable sensation of being watched. Across the living room while you scrolled through your phone. From the dining table as you washed dishes in the kitchen. During movie nights, when everyone else's attention was fixed on the television, you'd glance over only to find his eyes lingering on you for a split second before he looked away.
You tried to brush it off. Maybe he was just socially awkward. Maybe he zoned out more often than most people. Maybe you were reading too much into it.
But eventually, the feeling became impossible to ignore.
Your own home, once the only place you never had to think twice about relaxing, began to feel different whenever Lee Kang was there. Every room suddenly seemed to have a pair of unseen eyes tucked into the corner, following your movements with quiet, patient precision.
And no matter how many times you convinced yourself you were imagining it, you could never shake the strange, predatory feeling of being watched.
Even something as simple as leaving your room to grab a glass of water had become enough to send goosebumps racing down your arms.
You could feel his gaze before you even saw him.
It would follow you from the moment you stepped into the hallway, drifting over you with unsettling slowness, never obvious enough for anyone else to notice, yet impossible for you to ignore. It wasn't a quick glance or absent-minded curiosity. It lingered, tracing your movements from head to toe with a quiet intensity that made your skin crawl. Every trip to the kitchen felt like walking onto a stage where you hadn't agreed to be seen.
And Lee Kang's unnerving behavior didn't end with those piercing eyes.
More than once, you caught him standing inside your bedroom.
The first time, he claimed he had been looking for the bathroom after taking a wrong turn. The second time, he awkwardly muttered something about searching for your brother. By the third, you stopped believing the excuses altogether.
Each time, he always seemed to be standing near your dresser, the one where you kept your clothes. You tried to convince yourself it was nothing. Until you realized some of your underwear had gone missing.
After checking every drawer twice and searching the laundry basket for the hundredth time, you finally worked up the courage to tell your mom. You admitted that Lee Kang made you uncomfortable, that something about him had felt wrong from the very beginning, and that you couldn't shake the feeling he was crossing boundaries no one else seemed willing to acknowledge.
She listened, then she sighed. "He's just a quiet boy."
That was all. Somehow, Lee Kang had already won your parents over with his reserved, polite demeanor. He always greeted them respectfully, thanked your mother for every meal, offered to help clean up afterward, and had earned endless praise for helping your brother pass his coding class. To them, he was thoughtful, mature and well-mannered.
Then it happened. The very thing you had quietly dreaded ever since Lee Kang became a regular in your home.
Your parents decided he would tutor you.
The idea came about so casually that it almost made you sick. During dinner, Lee Kang had mentioned how exhausted he was from juggling multiple part-time jobs alongside university. Your father, impressed by his work ethic and still grateful that he'd helped your brother pass his coding class, immediately saw an opportunity.
"You could just tutor her instead," he'd suggested with a smile. "We'll pay you more than all those jobs combined."
You had laughed at first, convinced he was joking. He wasn't.
A few days later, your mother walked into your room wearing the same excited expression she always had whenever she thought she'd solved one of your problems.
"Good news," she announced cheerfully. "Lee Kang accepted. He'll start tutoring you next week."
For a moment, you heard nothing.
A high-pitched ringing filled your ears as the words settled in. Your chest tightened, your thoughts becoming sluggish beneath a wave of disbelief. It felt as though all the air had been pulled from the room.
"...What?"
Your mother continued talking, oblivious to the panic creeping across your face.
"He'll come over a few evenings a week. This is wonderful, sweetheart. He's such a bright young man—"
"Are you out of your mind?" you blurted, your voice breaking between uneven breaths. "I already told you he makes me uncomfortable! He's weird, Mom!"
She frowned immediately.
"Oh, don't start this again."
"No, you're not listening to me—"
Before she could finish, a gentle knock interrupted the argument.
The bedroom door had been left slightly ajar, Lee Kang stood on the other side.
His eyes found you first. Your chest rose and fell with sharp breaths, your face flushed with frustration, your hands trembling at your sides. He studied you for a heartbeat longer than necessary.
You could have sworn the corner of his mouth twitched. Not enough to call it a smile. Just the faintest hint of one before vanishing into his sugar-coated face.
He shifted his attention to your mother, his expression settling back into its usual quiet politeness.
"Um..." he began softly, rubbing the back of his neck. "I just wanted to let you know... I quit all my part-time jobs. Since we made our agreement, I figured I'd commit to this full-time."
His gaze drifted back to you for the briefest moment.
"Is... everything okay?"
A bitter scoff escaped before you could stop it.
Unable to bear the sight of him any longer, you tore your gaze away and looked out the window instead. The trees outside swayed gently beneath the evening breeze, their leaves rustling softly in the fading light. You focused on the movement, desperately trying to let the cool, familiar scene smother the anger burning through your veins.
Behind you, your mother let out an awkward laugh.
"Oh, everything's fine," she assured him quickly, waving a dismissive hand. "She's just overwhelmed. She agreed to the tutoring."
The lie made your stomach twist. You didn't turn around.
You heard Lee Kang murmur a quiet, "I see," before the floorboards creaked beneath his footsteps. The bedroom door clicked shut a moment later.
Only then did you allow yourself to blink.
Your vision blurred as tears stung the corners of your eyes. You hated it.
You hated that no matter how many times you tried to explain yourself, no one seemed willing to believe you. To everyone else, Lee Kang was simply a quiet, hardworking young man who had gone out of his way to help your brother and was now sacrificing his time to help you as well.
To them, you were being dramatic.
Your mother moved closer, her voice softening.
"Sweetheart..." she sighed. "You need to have a little empathy for him."
You stayed silent.
"He's shy. Socially awkward, maybe. Not everyone is good with people."
Still, you said nothing.
"Imagine how hurt he'd feel if he knew you thought these things about him."
You bit the inside of your cheek until it hurt.
Because no matter how desperately you wanted to tell her that she was wrong, that something wasn't right, that every instinct in your body was screaming at you, you already knew how the conversation would end.
With Lee Kang earning more sympathy, and you being told you were imagining things.
-
The first tutoring session arrived sooner than you would have liked.
Lee Kang was already seated next to you by the time you reluctantly entered your bedroom, your textbooks tucked beneath your arm. The silence between you stretched on as you settled into your chair, refusing to acknowledge him.
A ceramic mug slid into your line of sight.
"I made you coffee," he said quietly.
You looked down. Your favorite order, exactly how you liked it.
For a second, you simply stared at the cup before your eyes drifted back to him. You couldn't remember ever telling him how you took your coffee. He didn't seem to notice your hesitation.
"Your mom thought we should go over literature first," he continued, carefully arranging your textbooks into neat piles. Every movement was precise, almost methodical, as though he'd rehearsed the routine beforehand.
You remained silent, your disinterest written plainly across your face.
When he finally looked up, your expression seemed to make him pause.
He let out a quiet breath before he speaks up,."I wanted to apologize."
His voice was as soft as ever, lacking its usual monotony.
"I accidentally overheard your conversation with your mom the other day." He hesitated before continuing. "I... didn't realize I was making you uncomfortable."
For the first time since you'd met him, there was something different in his eyes.
They weren't empty and distant. They held an almost desperate sincerity, as if your answer genuinely mattered to him.
"I know we didn't get off on the right foot," he said, folding his hands together. "I just hope these sessions can give you a chance to know me better," He makes a small pause. "...To give us a second chance."
The choice of words made something inside you tighten.
Us.
His gaze lingered on yours, unwavering, patiently waiting for a response.
You frowned.
It was strange seeing this side of him. Softer, more expressive. More... human than the unnerving, silent figure you'd grown accustomed to avoiding. Against your will, your mother's words echoed in the back of your mind.
He's just shy.
Have a little empathy.
Maybe you've judged him too quickly.
You looked away, taking a slow breath as you gathered your thoughts.
Maybe... Maybe you really had been too harsh.
After a long moment, you let out a quiet sigh before giving him a reluctant nod.
"...Let's just start."
For the first time since entering the room, you turned your full attention toward him.
Across the table, Lee Kang smiled. It wasn't wide and it barely lasted a second. But somehow... It looked less like relief, and more like satisfaction.
-
The following weeks passed in a comfortable haze.
Every tutoring session blended seamlessly into the next. Lee Kang never crossed a boundary, never lingered too close, and never gave you another reason to doubt him. He kept a respectful distance, patiently guiding you through each lesson while conversations flowed with surprising ease.
Slowly, almost without realizing it, you found yourself letting your guard down.
The unsettling first impression he'd left behind began to blur around the edges, replaced by the quieter sides of him you discovered after every lesson. You learned that he preferred rainy days over sunny ones because they made it easier to write. That he almost never listened to music while studying. That he had a habit of tapping his pencil whenever he was searching for the right word.
And that he loved literature.
It quickly became your favorite subject to study together, not because you struggled with it, but because it was the only time Lee Kang truly came alive. His usually reserved voice gained warmth whenever he spoke about novels or poetry, and discussions that were meant to last half an hour somehow stretched into two.
He had once admitted, almost shyly, that writing was his greatest passion.
You believed him without question.
One evening, he'd even read one of his own poems aloud from the worn brown leather notebook he carried everywhere. You'd never forgotten the way his eyes had lit up with quiet pride as he read each line. It was the first time you'd seen genuine emotion break through his otherwise composed exterior.
Your parents noticed the change too.
They seemed relieved that you'd finally warmed up to him, convinced their judgment had been right all along. They'd trusted Lee Kang from the very beginning, but seeing the two of you chatting comfortably after lessons was enough for them to stop worrying altogether.
Soon, they no longer felt the need to stay home during tutoring sessions.
It became normal for the house to be left entirely to the two of you.
—
Another lesson begins much like the others. Today's topic is literature.
Halfway through organizing the books, Lee Kang rises from his chair. "I'll be right back," he says quietly. "Bathroom."
You nod without much thought.
As soon as his footsteps disappear down the hallway, you take another sip of your drink and absentmindedly skim through today's reading material. A small smile tugs at your lips.
Literature always brings out the most talkative version of him.
Your thoughts drift back to the afternoon he reads one of his poems aloud, his fingers gently tracing the edges of that familiar brown leather notebook. He lets you listen, but never once allows you to hold it yourself, always closing it the moment he finishes reading.
You tease him about being so secretive. He only smiles before tucking it back into his bag.
Your let your eyes wander across the table, stopping when you see the notebook there.
He must have forgot it. Your gaze flicks toward the hallway. When a deafening silence fills your ears, a quiet laugh escapes you before you can stop it.
"Curiosity really is going to kill me..."
Reaching across the table, you carefully pick up the brown notebook.
It's heavier than you expect.
The leather cover is worn smooth from years of use, its edges softened and creased as though it has accompanied him everywhere he goes. It's beautiful in the way only well-loved things can be.
You open it carefully. The first several pages are exactly what you expect, poems.
Some are handwritten so neatly they could have been printed, while others are hastily scribbled with corrections filling the margins. You can't help but smile as you remember him reading a few of them aloud.
Then, as you continue turning the pages, your fingers stop.
This isn't poetry. The handwriting is denser. Longer entries fill the page from top to bottom; each one neatly dated in the corner.
A diary.
Your stomach tightens. You should close it, you know you should, it was his privacy. But curiosity tugs harder than your conscience.
Glancing toward the empty hallway one last time, you bite your lip before lowering your eyes to the first line.
And you begin to read.
"I met her brother today."
"He's such a dumbass compared to her."
Your eyebrows knit together the moment your eyes catch the mention of yourself. Confusion crashes over you like an overflowing river.
This wasn't a diary. It was a collection of reports.
You flip to the next page.
"I met her parents through her brother today. She tried to talk to me… Cute."
Your heartbeat stutters.
Another page.
"I finally gained her parents' trust by helping her stupid brother pass."
Another.
"I can't resist staring at her."
Another.
"She catched me looking today. She looked away first."
Your breathing grows uneven as you keep turning the pages.
Each entry is dated, his writing shortening gradually. Like observations written by someone documenting an experiment.
"I gained her trust too. Easier than I thought."
Your fingers tremble. No. No, no, no... This can't be happening.
You hurriedly flip to the next page before a sharp thud stops you in your tracks.
The sound of the front door closing echoes through the house as a sharp gasp leaves your lips. The notebook slips from your hands, landing on the table with a heavy smack as you whip your head toward the hallway.
Lee Kang stands in the doorway, perfectly still. His expression is as calm as it has always been. As though nothing in the world is out of place.
He looks from the notebook... to you.
"What are you doing?" His voice is quiet, almost gentle.
"I was just—" The words catch in your throat.
You snatch the notebook from the table and place it back on top of the stack of books, your trembling hands desperately rearranging them into a neat pile.
"I was... rearranging the table." You force out a shaky laugh that even you don't believe. "I'm sorry, I—"
A short laugh cuts through your frantic explanation. It isn't loud, but it doesn't sound embarrassed, it’s rather amused.
"Why," he asks softly, "would you apologize for that?"
He starts walking toward you with slow, unhurried steps, each one so measured it feels almost calculated. Your eyes remain fixed on the books scattered across the table, too terrified to look up. If you meet his gaze now, you're certain he'll read every ounce of panic written across your face.
The footsteps come to a stop beside your chair.
He's close enough that you can feel his presence looming over you, the silence stretching unbearably between the two of you. Your fingers curl against the edge of the table as you force yourself to keep your breathing steady.
When he finally speaks, his voice is quieter than before, dropping into a tone that sends a chill down your spine.
"...Unless," he murmurs, "you were reading something you weren't supposed to read?"
Your breath catches, leaving your lungs in short, shaky bursts. Hidden beneath the table, your hands tremble uncontrollably in your lap as your mind races for a way out.
Don't think, just run.
The thought flashes through your mind, and your body acts before fear can root you to the spot.
You shoot up from your chair and shove him with every ounce of strength you have. The sudden force catches him off guard just enough for you to dart past him, your chair scraping violently against the floor as you lunge toward the door.
You barely make it two steps before a sharp tug at the back of your head jerks you to an abrupt stop. Pain blooms across your scalp as your hair is pulled taut, forcing your body backward before you can reach the handle.
Before you can regain your footing, he's already on you.
With alarming ease, Lee Kang forces you backward, and you stumble onto your bed. The mattress dips beneath your weight, the same bed that had always been your safest place, now suddenly feeling like a trap.
Panic surges through you. You lash out instinctively, kicking and twisting in a desperate attempt to put distance between the two of you. He catches your movements with frustrating precision, pinning you before you can slip away.
A hand clamps around your neck as your breath hitches.
The room spins as instinct takes over, your hands flying to his wrist as you try to pry him away. Every breath comes shorter than the last.
He lets out a quiet scoff, shaking his head as though you'd merely inconvenienced him.
"Stupid bitch," he mutters, disappointment lacing his voice. "And here I thought everything was going so smoothly."
Your vision blurs as you cling to his wrist with trembling fingers.
"P-please..." you manage, your voice strained and barely audible. "Don't... don't kill me."
For the first time since you'd met him, something in Lee Kang's expression shifts.
Not anger, nor satisfaction, something far more unsettling.
His grip eases just enough for air to rush painfully back into your lungs.
You suck in a ragged breath, coughing as your chest rises and falls in frantic, uneven rhythms.
A small sigh escapes him, almost... relieved.
"Oh, baby," he says softly, tilting his head as though the very idea had caught him off guard. "I would never."
The corners of his mouth lift into a faint smile. "I love you far too much for that."
The words don't comfort you, they hollow you out.
Your eyes widen as you stare at him, searching desperately for some sign that this is a joke, that the quiet, awkward tutor you've spent weeks convincing yourself to trust is still somewhere behind those familiar features.
Instead, you find only calm certainty. With relentless precision he grabs your shorts along with your panties and yanks them downwards, leaving you bare and defenseless.
You cry out to tell him to stop, but his hand tightens around your neck, reducing your voice into helpless hitches as tears stream down your cheek.
A spank cuts through the room, making you yelp when you feel a sharp pain across your pussy.
“Stay still.” There wasn't a trace of anger in his voice, only quiet, merciless certainty.
When he lowers his trousers and lets his flushed cock out, it unravels the last thread of composure you're clinging to. Your heartbeat spikes, each frantic thud echoing louder than your own thoughts.
He briefly grazes himself against your folds before pushing abruptly, eliciting a pained gasp from you. He fills you all the way to the brim with a groan under his breath before the corners of his mouth curl upward. “You’re gripping me so well, such a good slut.”
You feel him withdraw to the tip before thrusting harshly again. Tears stream down your face as your nails dig into the hand still gripping your neck, and he lets out a strained hiss, along with a twitch of his cock. He was enjoying the painful scratches you were giving him.
Every reaction, every touch from you was pleasurable for him, he had wanted this for so long.
He quickens his pace as you feel yourself growing hazier. He moves closer to your swollen, parted lips, smiling warmly as if nothing is wrong. Then he kisses you, unhurried, before resting his forehead against yours like this is something intimate and normal. “I love you so… so much,” he murmurs. “I’m going to prove it to you.”
When you feel his cock twitch continuously inside of your squelching pussy, you gather up your last strength to shake your head frantically as you whine.
“Shh. It’s okay. It’ll be over soon.” His voice stays steady, like he’s stating a fact rather than trying to calm you down.
With one final thrust, he presses deep into you as he releases his cum against your womb. He lets out rigid pants, trying to steady himself, before slowly releasing his grip around your neck. You let out worn out coughs as you feel his cum drip out from your hole. Between ragged breaths, sobs begin to overtake you, each one harder to suppress than the last. Your entire body trembles as you curl in on yourself, unable to steady your breathing.
Lee Kang watches you in silence for a long moment. Then, with a tenderness that makes your stomach turn, he brushes a stray strand of hair away from your face.
"You did well," he says quietly, sounding almost proud. "I knew you'd get through it."
