Chapter Text
The cafeteria buzzed with the usual midday chaos, trays clattering, people talking at once, some totally abandoning their food to cause chaos. Midst all this, Anxin had his head and arms sprawled across the sticky table like a deflated balloon. He let out a long groan which he felt vibrating right back into his body.
“I’m done. I’m actually done. If my grades drop any lower I don't think I'll past this semester. I don’t even know how I’ve survived this long.”
He lifted his head just enough to steal a fry from Suren’s tray.
“Should I just step in front of a car?”
“Hey! That’s my fry, you thief,” Suren yelped, swatting at Anxin’s hand. Anxin dodged and took another one, popping it into his mouth.
Xinlong reached over and started petting Anxin’s back in slow circles like he was calming a housecat. “There, there. You’re not dying yet.”
Zihao from a few chairs far, glanced up from his phone and pointed at the far corner of the cafeteria. “I heard that guy is insane at biology. Like top of his class. You should ask him to tutor you.”
Anxin followed the point of Zihao’s finger. His gaze landed on Lee Sangwon, unfairly gorgeous, currently reading a thick book at a table by the window.
The light caught the sharp line of his jaw, the way his dark hair fell just slightly over his eyes as he turned a page. Anxin’s brain short circuited for a solid three seconds.
“Hell no,” he said, voice cracking on the last syllable. He threw both hands up in surrender.
“He’s too hot. You’ll literally catch me staring at his lips the whole time instead of actually listening to whatever he's explaining. I’d fail harder.”
The table collectively facepalmed mentally. "Crazy," Jiahao said with mouth full. Kaiwen just sighed like he’d expected nothing less.
“Bro,” Kaiwen muttered, deadpan, “there goes your college degree.”
Anxin turned around, chair scraping and lunged halfway across the table to grab Kaiwen in a strangle. “Take. That. Back.”
Laughter erupted as Kaiwen dodged, yelling for mercy. But Anxin’s eyes flicked back to Sangwon one more time.
The senior hadn’t even looked up. Of course he hadn’t. Anxin slumped back into his seat, stealing yet another fry. “I’m doomed,” he whispered.
Anxin thought hard, finding no other way he decided to ask Sangwon. What's the worse thing that could happen.
He waited until Sangwon was alone, tucked in the quiet corner of the library lounge with a highlighter between his teeth. Anxin’s heart slammed against his ribs like it was trying to escape.
“Hey... senior?” Anxin cleared his throat. “Would you mind doing me a favor?”
Sangwon looked up slowly. A few dark strands of hair had fallen across his forehead; he tilted his head and shook them back with one casual flick of his fingers.
The motion was so unfairly smooth that Anxin’s eyes tracked it then up to those sharp eyes now locked on him. Anxin froze. Look at his eyes. Don’t panic. Don’t stare at his lips. Eyes.
Sangwon’s lips curved into a small smile. His eyes crinkled into soft crescents. “Yes?” The single word was warm, “How can I help you, Anxin?”
Hearing his name in that low, calm voice almost short circuited Anxin’s brain. He knows my name.
“I-uh-I actually need help with biology,” he rushed out. “I’m really bad at it. Like catastrophically bad. I heard you’re...super good? So if you could maybe spare some time to tutor me? Just until the exam in two weeks? Please?”
Sangwon studied him for a bit, head tilting slightly to the side. Then he leaned back in his chair, arms crossing loosely over his chest. “Sure,” he said simply.
Anxin’s face lit up. “Really? Thank you-thank you so much-”
“But,” Sangwon cut in, “What do I get out of it?”
Anxin blinked. “...Huh?”
Sangwon’s smile widened, the tiniest bit, enough to show he was enjoying this. “I’m not saying it has to be big.”
Anxin’s mouth opened, closed and opened again. “Uhm. What would you like? I’m-I’m really desperate here. Like failing college desperate. I’ll do anything.”
Sangwon’s gaze flicked over him, “Anything?”
Anxin nodded so fast he nearly gave himself whiplash. “Anything. Seriously.”
A soft huff of amusement escaped Sangwon. He pulled out his phone. “Alright. I’m free tomorrow afternoon. Meet me at my dorm.”
Anxin’s brain malfunctioned . “...Your dorm?”
“Yes,” Sangwon tapped at his screen, then held it out. “Give me your number. I’ll text you the building and room number.”
Anxin recited his digits on autopilot, watching Sangwon type them in with slender and pretty fingers.
Sangwon stood, slinging his bag over one shoulder. He gave Anxin one last look then walked away without another word.
Anxin stood there. He was going to Lee Sangwon’s dorm. Alone. He was going to die.
Anxin buried his face in his hands and let out a muffled, hysterical laugh.
That night, Anxin’s phone buzzed non stop. He flopped onto his bed, blankets half kicked off and opened the group chat.
Anxin: what if i just died in my sleep tonight
peacefully
and then i wouldn’t have to go to tutoring tomorrow
problem solved
The replies came fast.
Zihao: girl ur hair will all fall out before u hit 20 if u keep
worrying like this.
stress is literally killing ur follicles rn
Suren: lmao rip to the hairline
Xinlong: dramatic ass, just go
he’s hot and smart, worst case u fail biology but get
an eye candy
Kaiwen: if u die in ur sleep the snacks u hid under ur pillow r
mine
Anxin: yall are the worst friends ever
im blocking u all
He didn’t block anyone. Instead he buried his face in the pillow and passed out.
The next afternoon came way too quickly.
Anxin stood outside Sangwon’s dorm door like a statue that had forgotten how doors worked.
He’d been there for a solid five minutes staring at the plain woodendoor. Knock? Ring the bell? Just walk away and fake your own death? Options. We have options.
His hand hovered. Dropped. Hovering again.
Suddenly a cold palm landed firmly on his shoulder.
Anxin yelped, spun around so fast he nearly tripped over his own feet and threw his arms up in the world’s most pathetic boxing pose.
Sangwon stood there, keys dangling from his fingers, shoulders shaking with silent laughter. He pressed the back of his hand to his mouth.
Anxin’s dropped his arms instantly. “I-I-” he stammered.
Sangwon lowered his hand, still smiling, “Look at you. All cute and nervous. Couldn’t even hit the bell?”
“I am not nervous,” Anxin shot back, too defensive.
“I knew the door was locked and no one was inside, so I was ..waiting for you to come back. Obviously.”
Sangwon tilted his head, amusement flickering in his eyes. “Sure.”
He brushed past Anxin, close enough that their arms grazed and slid the key into the lock with one smooth motion. The door swung open.
Anxin hurried in after him, still talking. “I’m telling the truth! I was being logical-”
Sangwon stopped abruptly in the middle of the small entryway. He turned slowly until he was facing Anxin fully. Anxin froze mid-sentence.
Sangwon looked right into his eyes, unblinking, “I never said you were lying,” he said quietly.
Sangwon held his gaze long enough for Anxin’s throat to go dry then turned and walked deeper into the room. “Coming?” he called over his shoulder, completely casual
Anxin stood there, God. He was really going to die here. Not from failing biology. From whatever Sangwon was about to do to him with just a look.
He swallowed hard, forced his legs to move, and followed. The door clicked shut behind them.
Anxin was officially inside Lee Sangwon’s dorm. Alone.
Sangwon motioned toward the open door at the far end of the small dorm. “Come on in.”
Anxin hesitated. “Wait-we’re studying in your room? Not.. like the dining table or something?”
“You want me to drag all my books and notes out here? We can do that if you really prefer here.”
“No, no!” Anxin waved his hands frantically. “Your room is fine. Totally fine.” He stepped inside before he could overthink it further.
God. He was actually entering Lee Sangwon’s bedroom. What kind of miracle had he accidentally performed in his past life to deserve this?
The room was tidy in that effortless way, books stacked neatly on the desk, a single lamp casting warm light, bed made with precision.
It smelled faintly like whatever cologne Sangwon wore. This is where he sleeps. Where he wakes up. Where he-
Sangwon was already talking, pulling out a chair for Anxin at the desk and flipping open a thick notebook. Anxin tried to focus. He really did.
“...so we’ll start with the basics of the respiratory system since that’s where most people fumble during the exam”
But Anxin’s eyes kept drifting. Sangwon’s lips were moving, parting just enough to show the quick flash of his tongue. When he paused to think, he pouted for half a second while searching for the right word and Anxin’s stomach flipped.
“Anxin. Anxin-are you listening?”
“Huh? Yes! Of course. Continue.”
Sangwon arched a brow. “Okay. Tell me what I just said.”
Anxin scrambled. “Respiratory system.”
Sangwon waited. “...What about it?”
A soft sigh. Sangwon leaned back, arms crossed. “Let me ask you a question then. What helps to prevent foreign particles from entering the lungs?”
Anxin thought hard. He knew this one. “Flagella?”
Sangwon folded his notebook into a neat rod shape and tapped it gently against Anxin’s head.
“Oww!”
“Cilia, silly.”
“Aren’t they the same thing?”
“Of course not.” Sangwon’s tone was patient.
“Flagella can locomote freely and independently. Cilia beat in coordinated waves but stay anchored. There is a great difference."
Anxin rubbed his head dramatically.
“You’re not listening, Anxin,” Sangwon echoed in disappointment, “I thought you were desperate.”
“I am desperate, Sorry, promise I’ll pay attention from now on.”
Sangwon studied him for a long moment. “You told me you’d do anything, right?”
Anxin’s pulse kicked up. “...Yeah?”
“Okay,” Sangwon’s voice dropped low. “Give me your hands.”
Anxin extended them without thinking. Sangwon caught his wrists gently guiding Anxin’s hands upward until they settled around Sangwon’s own neck.
He tried to yank his hand back on instinct. Sangwon caught his wrists again, firmer this time and pressed it back in place. “Uhm...what are you doing?”
“Anxin,” Sangwon’s voice was super low, “The thing you’re touching right now is called the trachea.” Anxin’s eyes went wide, pupils blown. He could feel the cartilaginous rings.
“Numerous hair like structures called cilia are located here.They trap particles out of the airway.” Sangwon took two of Anxin’s fingers and slid them a little higher, just under his jaw.
“This is the larynx.” Anxin’s breath hitched. “It’s formed by the arytenoid, cricoid, and thyroid cartilages.”
Then Sangwon guided Anxin’s whole hand down until his palm rested right over the prominent bump of Sangwon’s Adam’s apple.
Anxin stared. It was so clear, so defined. When Sangwon swallowed, slow, Anxin felt the bob against his skin. A tiny, involuntary sound escaped his throat.
“Thyroid cartilage causes that elevation in the throat for males,” Sangwon continued, voice a little rougher now, “Which is the Adam’s apple.” Anxin could only nod.
Sangwon said his name, “Anxin... Anxin...” Anxin whimpered without meaning to.
“My voice is produced here.” Sangwon tapped lightly where Anxin’s fingers still rested, “So it’s also called the voice box.” He slid Anxin’s hand just a fraction higher.
“Just above the larynx is the epiglottis. It acts like a protective lid to cover the larynx and trachea when you swallow. Directs food and fluids into the esophagus instead of the airway and prevents choking.”
Sangwon finally released Anxin’s wrist. Anxin quickly moved his hand away. “Did you get what I said so far?” Anxin nodded again helplessly.
Sangwon’s lips curved, “Good.” He leaned in the tiniest bit closer to Anxin.
“Because if you’re going to survive this exam...you’re going to have to pay very close attention to what happens when the body reacts.”
Anxin’s mouth went dry. Sangwon’s eyes flicked down to Anxin’s lips then back up.
Sangwon pulled back completely, breaking the contact so suddenly. He turned to face his open books on the desk.
Anxin sucked in an embarrassingly loud, shaky breath like he had forgotten how lungs worked. He stared at Sangwon. Sangwon didn’t look up right away. He just flipped a page, voice calm.
“What chapters are on your exam again?”
Anxin managed to put some words together. “Respiration...and digestion.”
“Hmm,” Sangwon nodded, still not turning. “The structure of the respiratory system is easy to memorize once you visualize it. I’ll send you some 3D models and labeled diagrams later, learning visually helps. Too bad we can’t just open up our chests and look inside, right?”
He finally glanced over his shoulder, eyes locking straight onto Anxin’s. Anxin blinked. Was that... a joke? Sangwon’s expression was perfectly neutral but there was the tiniest twitch at the corner of his mouth.
Anxin laughed anyway, too loud. “Yeah... haha...that’d be convenient.” Sangwon’s gaze lingered for a beat longer before he turned back to the notes.
“The real challenge isn’t the anatomy. It’s understanding inspiration and expiration. People get the mechanics confused all the time.”
Without warning, he scooted his chair closer. The legs scraped against the floor, now their knees were almost touching. Anxin’s heart immediately went into arrhythmia.
Sangwon reached out. One hand settled flat on Anxin’s chest, right over his sternum. The other slid partially around to his back between his shoulder blades.
They were so close Anxin could count Sangwon’s eyelashes. He could smell the faint mint on his breath.
Yeah, Anxin thought dimly. I’m seeing the Grim Reaper and he's wearing Sangwon’s face.
“Anxin,” Sangwon said softly. “Take a deep breath in and hold it. Don’t let it out yet.”
Anxin obeyed on autopilot. Lungs filled. He locked his diaphragm, cheeks already burning. Sangwon’s hand on his chest pressed lightly, feeling the rise.
“When you inhale your diaphragm contracts and flattens downward. That increases the vertical diameter of the thoracic cavity.” His fingers shifted, tracing the lower edge of Anxin’s rib cage.
“The ribs elevate too. External intercostal muscles contract. Increases the anterior-posterior and lateral diameters.” Anxin was struggling. Air burned in his lungs. Sangwon’s eyes flicked up and the corner of his mouth lifted just a fraction.
“You can exhale now.”
Anxin let it out in a rush, gasping, he felt dizzy. Sangwon kept his hands where they were for one more second.
“Expiration is mostly passive. The inspiratory muscles relax. Elastic recoil of the lungs and chest wall pulls everything back. Diaphragm comes upward, thoracic volume decreases, intrapleural pressure rises, air is forced out through the nostrils lastly the lung volume drops.”
He talked like he was reading from a textbook, but his thumbs were still brushing tiny, absent circles over Anxin’s shirt. Then he finally removed both hands.
Anxin almost whimpered at the loss. “Do you understand?”
“Y-yes.” Anxin’s voice cracked.
“Great.”
Sangwon didn’t move his chair back. Instead, he leaned forward again, this time both hands landing low on Anxin’s stomach, palms flat just below his navel. Anxin jolted so hard the chair creaked.
Sangwon looked straight into his eyes, unblinking. “Next time... we’ll cover digestion. What happens when something enters the mouth... travels down the esophagus...and reaches here.” His fingers pressed lightly right over Anxin’s abdomen.
Anxin nearly slid off the chair. His brain stopped functioning. Sangwon was doing this on purpose. One hundred percent on purpose.
Sangwon finally leaned back, casual again, picking up his pen like nothing had happened.
“Review the 3D models tonight. We’ll go over the rest tomorrow.” Anxin could only nod. His words long gone.
Anxin didn’t dare walk home right away. His legs straight up betrayed him the second he stepped out of Sangwon’s dorm building, knees wobbling like they’d forgotten what they do. He had to lean against the wall for a solid minute, breathing like he’d run a marathon.
The next day in the cafeteria, Anxin looked half dead. Red eyes, dark circles deep, hair a tragic mess.
He had barely slept, every time he closed his eyes, it was Sangwon’s voice murmuring about diaphragms and elastic recoil, Sangwon’s palms pressing into his ribs, Sangwon’s Adam’s apple bobbing under his fingers.
He’d tried to study. Opened the 3D respiratory models Sangwon sent. Made it through maybe ten minutes before the memories crashed back in and his face heated up all over again.
Evil. Pure evil.
Jiahao slid into the seat next to him and immediately hooked an arm around Anxin’s neck from behind, pretending to strangle him in a headlock.
“Gah! Not the throat!” Anxin yelped, struggling until he broke free.
Jiahao grinned, “You didn’t tell us what happened yesterday at tutoring.”
Suren's mouth full of the cafeteria’s sad, cold pizza, “Yeah, spill. You look like you got run over by a truck.”
“Nothing happened,” Anxin said way too fast, shoving a spoonful of whatever mystery mush was on his tray into his mouth.
Kaiwen leaned forward, smirking. “That’s why you didn’t sleep all night and now you look like a panda?"
Xinlong burst out laughing, loud, obnoxious, drawing stares from nearby tables.
“I was studying!” Anxin protested, smacking Xinlong on the back of the head. “Ow-hey !”
Just then, the cafeteria noise dipped for a split second. Sangwon was walking straight toward their table.
Everyone froze.
Sangwon never came over here. He usually ate alone in his corner or with his own group of seniors across the room. Heads turned. Whispers started.
Anxin was forced to look up. Sangwon had new glasses today, thin, black frames that somehow made his eyes look sharper, more intense. Anxin’s brain malfunctioned. Again.
Sangwon stopped at the edge of their table, voice low and calm. “Same time today?” Anxin could only nod, completely mute.
Sangwon’s gaze flicked down to Anxin’s face, lingering on the dark circles, the flushed cheeks. A tiny, knowing smile tugged at his lips.
“We’ll study what happens when you swallow today, yeah?” He said it in a teasing tone. Then he turned and walked away, leaving dead silence behind.
The table exploded the second Sangwon was out of sight.
“ANXIN. SWALLOW WHAT?!”
“Why did he say it like that?!”
“What did you swallow yesterday?!”
Anxin’s face red. “NOTHING! I swallowed NOTHING!” He shot up so fast his chair screeched and bolted toward the bathroom like his life depended on it.
His friends scrambled after him, Jiahao cackling, Suren yelling questions, Xinlong still wheezing. Kaiwen snatching the half eaten slice of cold pizza on his way out.
Anxin was back in hell. Or heaven.
Deja vu hitting hard, Sangwon leaning over the desk, tidying his notes with that calm precision, pen tapping once against his lower lip as he decided where to start.
Anxin satstraight on the chair, every tick of the wall clock drilling into his skull like a countdown to execution.
Sangwon finally looked up. “So, Anxin. Do you have a rough idea about the alimentary canal?”
Anxin swallowed. “Yeah. I mean-I passed my previous exams.”
Sangwon hummed, thoughtful. He held the pen to his temple for a second, then set it down. “Stand up for a second.”
Anxin blinked. “Huh?” Sangwon didn’t repeat himself. Just waited.
Confused, Anxin pushed the chair back and stood, his legs already shaky.
Sangwon’s hand moved fast, straight to Anxin’s zipper.
Anxin lurched backward so hard he almost tripped over the chair. “What the-?!”
Sangwon didn’t flinch. He simply sank to his knees in one fluid motion, eyes locked upward, calm and expectant.
“Anxin,” he said softly, fingers already moving towards the zipper again, “You said you’d do anything.”
“I-I did say that, but-” Anxin’s voice cracked. “Are you really going to do what I’m thinking?”
Sangwon tilted his head, gaze steady from below. “Tell me, Anxin. What exactly are you thinking?”
Anxin’s mouth opened then closed. Nothing came out. His pupils were shaking.
Sangwon took the silence as permission.
The zipper rasped down. Cool air hit his warm skin. Sangwon tugged Anxin’s pants to mid thigh in one smooth pull. Anxin’s hands flew to his face, covering it completely.
“Anxin,” Sangwon’s voice was gentle, almost commanding. “If you hide your face, how are you going to look and learn?”
This is it, Anxin thought hysterically.
I’m dead. This is the afterlife. Punishment for every filthy fantasy I’ve ever had about him.
He peeled two fingers apart just enough to peek through the gap.
Sangwon hooked the waistband of Anxin’s boxers next. Slid them down slowly. Anxin’s cock sprang free, already half hard from anticipation.
God. Am I really about to get blown by the Lee Sangwon?
Anxin didn’t move. Couldn’t. Every muscle locked. Sangwon wrapped warm fingers around the base first, just holding.
Anxin’s brain screamed: Do something. Anything. Please.
Then Sangwon leaned in. The very tip of his tongue touched the head.
Anxin’s eyes blew wide.
Sangwon spoke around it, voice muffled but clear enough. “We have taste buds distributed across the tongue. They help us perceive different tastes.”
He swirled just the tip over the slit. “Here- sweetness is detected most strongly.”
Anxin made a choked noise.
Is he seriously talking about biology right now?!
Sangwon angled the shaft slightly to the side, pressing it against the lateral edge of his tongue.
“Here-salinity is more prominent.”
Sangwon continued, slowly taking more into the wet heat of his mouth. Anxin’s hips jerked involuntarily, an embarrassing, high whimper escaped him.
Sangwon pulled back just enough to speak again, lips brushing the head. “With the same angle, a little deeper, sourness registers here.” He demonstrated, sliding forward again, cheeks hollowing slightly.
Then he withdrew completely, letting the shaft rest heavy and glistening against his lower lip. “Do you know where we feel bitterness most intensely?”
Anxin shook his head frantically. No. He didn't. His brain is a mush right now.
Sangwon didn’t wait for him to reply.
He took Anxin deeper this time, past the point where tongue met soft palate, stopping just before the throat. Not deep throating yet but close. Close enough that the muscles of his throat flexed visibly around the intrusion.
“Here,” Sangwon managed, voice distorted around the cock filling his mouth. “Bitterness.”
Anxin’s vision whited out at the edges. His knees buckled. He grabbed the edge of the desk behind him to stay upright.
Sangwon’s throat squeezed roughly and Anxin felt the desperate urge of orgasm building with zero movement but just from the heat and pressure, the knowledge that this was Sangwon. On his knees.
He was going to come like this, untouched, except for Sangwon’s tongue and throat and that knowing look still locked on his face.
Sangwon pulled off slowly, a thin string of saliva connecting them for one humiliating second before it snapped. He licked his lips once.
“Understand now?” he asked, voice rougher than before. “The alimentary canal starts here.” He tapped his own lower lip.
Sangwon didn’t give Anxin time to recover from the demonstration.
He simply leaned forward again, slow and took Anxin deeper this time. Not the full length but far enough that the head nudged the back of his throat. Sangwon’s cheeks hollowed as sank forward again in a steady, controlled rhythm.
Anxin’s head fell back. A soft, broken moan spilled out. Little helpless sounds he couldn’t stop, couldn’t quiet down. His hips twitched forward on instinct, chasing the heat.
Sangwon noticed immediately. He pulled off with a wet pop, lips glistening, eyes flicking up in warning.
Anxin whined, high and desperate.
“Tell me, Anxin,” Sangwon said, voice rough from use but still perfectly calm. “Which cartilages make up the larynx?”
Anxin blinked. Brain still in mush. Everything was scattered. Sangwon’s mouth inches away from where he needed it most.
“I-”
Sangwon didn’t wait for an answer. He took him again, shallower this time, just enough to tease, tongue curling lazily around the head.
“Yeah,” Sangwon mumbled around him, vibrations shooting straight up Anxin’s spine. “I taught you yesterday.”
Shit. Is he serious right now?
Anxin’s hands clenched at his sides. “Thyroid...”
Sangwon hummed as an encouragement. “...and?”
“I-I can’t remember-”
Sangwon pulled off completely. A thin strand of saliva stretched, still connected until he spoke.
“You only remember the cartilage I physically taught you about,” Sangwon’s eyes glittered. “That was effective, yeah?”
Shame crashed over Anxin like cold water. He’d literally forgotten basic anatomy because Sangwon had his hands on his throat yesterday. And now this.
Sangwon didn’t let the moment linger.
He leaned in again, took Anxin back into his mouth, deeper and faster. This time his hands clamped onto Anxin’s hips, fingers digging in hard enough to bruise, holding him still so he couldn’t thrust. He liked the control.
Sangwon’s tongue worked relentlessly, swirling over the slit, pressing flat along the underside, flicking until Anxin’s legs trembled and threatened to give out.
Anxin’s hands flew to Sangwon’s head, fingers threading into dark hair, holding on for dear life.
Time blurred. The wet sounds made anxin go crazy, the occasional graze of teeth was too much. Anxin came hard.
His whole body locked up, thighs shaking, a choked cry ripping out of him. He slapped both hands over his face, trying to hide the wrecked expression, the way his mouth hung open. When the aftershocks finally ebbed, he peeked through his fingers.
Sangwon was still on his knees.
Mouth open. Showing Anxin the thick white streaks coating his tongue, pooling at the corners of his lips. He looked so proud. Anxin’s stomach flipped.
“Hey-, I’m so sorry-please, just-” He thrust out a trembling hand, palm up, like he could somehow catch it or wipe it away. “Here throw it out.”
Sangwon didn’t move.
He just stared, eyes locked on Anxin’s after that he closed his mouth. And then swallowed.
Anxin screamed. An actual full volume scream escaped his throat.
Sangwon rose smoothly to his feet, wiping the corner of his mouth with the back of his hand like it was nothing.
“This,” he said, voice low, tapping his own throat lightly, “entered inside me by the peristalsis process.”