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“I know you can focus more, Renjun,” Renjun hears, and if he were in any other predicament where he had just a teeny, tiny bit more control over his own body, he might consider turning around and cuffing Doyoung over the ear. Renjun grits his teeth; his bastard professor even has the sheer and utter gall to sound bored out of his mind, like he’s lecturing some poor college freshman on basic taxonomy instead of reviewing code for the analyses on the finally fully-compiled dataset of results from all of the experiments that Renjun, his one and only PhD student, had painstakingly performed over the last eight months.
To Renjun’s dismay, Doyoung’s cock even reflects some of his disinterested sentiment, having the audacity to have softened a bit, and Renjun momentarily considers squeezing the ever-loving life out of his professor’s dick inside him. He decides against it the next second, silently coming to terms with the knowledge that doing so would only make Doyoung prolong this game (and thus Renjun’s torture) even more.
For better or for worse, Renjun can’t immediately recall how he got himself into this situation. It was high school chemistry that introduced him to the idea that molecules and molecular structures were cool. Books were cool too, and that was enough to motivate himself into grinding his ass off in preparation for college entrance exams, which (thankfully) paid off in the form of acceptance to a C9 university in China. Then, undergrad was what introduced him to the idea of synthesized molecules and the very important knowledge that there was lots and lots of funding specifically backing the research of synthesized molecules for the sole purpose of anti-aging. So, that’s what undergrad Renjun started to do: clean beakers and occasionally pipet some stuff for an anti-aging lab, which landed him on the authors list for a couple of publications. Then, he realized he liked what he was doing and wanted to do more of it, so he kicked himself in the ass every night studying English (or watching Modern Family, let's be real) for several months, scored a 118 on his TOEFL, and then landed himself a position in a PhD program on the northeastern American coast, fresh out of his Bachelor’s. (Renjun isn't a genius or anything; he just works hard and it helps that he's passionate about his work.)
Whether it was a blessing or a curse, his assigned PI--the man who would be advising him for the entirety of his degree--was the rather interesting (and in Renjun’s opinion, smartass, asshole, power-hungry) Doyoung Kim.
Assistant Professor Doyoung Kim had a certain reputation among not only the department or even the university; for one, depending on who you asked in the anti-aging science community, they either thought he was a prodigy, or that he was a giant fraud and faked all his data on his way to the top. It was almost unheard of for any scientist in any field to have achieved the lifelong goal of becoming a Principal Investigator and heading their own lab by their mid-thirties; most of Doyoung’s similar-aged peers were still in postdoc training or schlepping their way as a staff scientist in a lab until their own PI retired and they got to inherit the lab themselves.
Within campus, Doyoung was known as That One Young And Handsome Professor; his age made it so that he wasn’t as greyed out, wrinkled, and sagging as the other professors, and his genetics made it so that his inky black hair, fair skin, and slim but strong profile had his wire-rimmed glasses transforming him into a polished, intelligent, well-mannered scholar instead of an awkward, antisocial, anxious nerd.
Within the department, Doyoung received ample respect, whether it was given to him automatically or warily. As expected, many others in the department were initially cautious, if not outright skeptical about him as a scientist and as a person. But, he was unassuming, unwavering, direct and concise almost to a fault, and had such a scarily natural propensity for the fine details in his work that he earned the trust of every scientist who'd given him a chance by experimental collaboration.
So, sure, Renjun definitely mirrored the professional respect his fellow scholars had for Assistant Professor Doyoung Kim, but that didn't change the fact that he also thinks the professor is an absolute fucking menace.
“Come on, you've been doing such a nice job tonight, Renjun.” Doyoung strokes Renjun’s side with one hand, fingernails lightly scratching and eliciting goosebumps over Renjun’s warm skin. His other hand gently massages the knob of Renjun’s hipbone. “You're such a good boy for me, I'm tempted to keep you right here for the rest of the night.”
Jesus fuck, Renjun thinks. His cheeks redden at Doyoung’s words, the head of his cock twitching in earnest against his lower stomach. A sense of desperation starts low in the back of his throat. One of the last things he wants is to be in this position for the remainder of the night. Assistant Professor Doyoung Kim, menace? In-fucking-deed.
In fact, the first time they met, Doyoung thought Renjun was a poor lost freshman.
“You’re in the wrong building, young man. The introductory biology labs are in the next building over. Get back to the main hall and keep on walking towards the H wing,” Doyoung had said not a moment after Renjun opened the lab’s door. The professor was sitting in front of a microscope, glasses resting atop his head, staring into the eyepiece as each of his hands maneuvered a pair of ultra fine forceps. He hadn’t even glanced up at Renjun once.
“What the hell?” Renjun had responded on instinct, staring incredulously at the professor. He’d seen the man’s photo online, so he knew he was in the right place.
Upon those words leaving his mouth, everyone else in the lab paused and stared; of course, everyone except Doyoung. They’d all given Renjun a brief look from the sound of him opening the door, though all of them had returned to current business as scheduled as soon as Doyoung opened his mouth, likely having accepted their PI’s truth of assuming Renjun was just another lost freshman.
“I’m your new PhD student, Christ,” Renjun replied. He didn’t know what to make of their first interaction, but he had a quickly growing feeling that the professor was going to be the type to drive him nuts, for some reason or the other.
“Oh?” Doyoung mused, raising an eyebrow slightly, the first reaction he’d given to Renjun’s presence and the first break from his statically neutral facial expression. “Then make yourself useful. Chenle, go show him how to use the autoclave. And make sure you don’t accidentally set off the fire alarm again.”
Before Renjun could protest--he knows how to use a fucking autoclave, what the fuck, and what autoclave would set off a fire alarm?--he was greeted by a blubbering kid who actually was a freshman and simultaneously not in the wrong building, before spending the rest of the day following around said freshman who was having a hard time awkwardly steering their conversations because his anxiety-inducing PI told him, the freshman, to teach the PhD student how to perform the most menial lab maintenance tasks; talk about power imbalance.
Anyways, it’d felt like an eternity before Doyoung let Renjun do some real science (“I am simply seeking reassurance that you possess basic lab safety and compliance competence,” Doyoung had explained casually when Renjun brought it up, because in his obvious opinion, having your PhD student scrub the necks of flasks was a waste of time and funding), but in reality, it was a mere few weeks. And then once those few weeks were over, Doyoung threw so much at Renjun that Renjun swore he’d been inflicted with physical whiplash (“I am simply stretching the limits of your competence,” Doyoung had explained like it was no big deal when Renjun brought it up that he was on his fourth night of four hours of sleep and so far into his fourth can of Monster for the day).
Despite it all, Renjun had done his best to keep up with it (and keep up he did), not only because he actually had his heart in his work, but also he constantly reminded himself that no matter how the professor made him feel (“You’re here because you’re passionate about research, correct? So I am simply allowing you to do as much research as your passion dictates,” Doyoung had framed it blankly, when he found Renjun napping on the dusty lab floor one morning with his hair stuck to the crust in his eyes), he should be grateful that he was lucky enough to land one of this generation’s greatest minds in the field as his mentor.
Perhaps Doyoung was proud of him, though he never explicitly expressed it past easing up on Renjun and subsequently giving him free(ish) rein to drive his own experiments.
It then began with couple hour-long chats reviewing the current state of research into the synthesis of senolytic compounds before delving into in-vivo versus in-vitro methods of inducing cellular senescence. Soon, they’d still be talking past five or six o’clock, and then Doyoung would swivel around in his office chair, unlock the largest drawer of the cabinets behind him, and pull out his emergency brandy (“You’re old enough to drink, yes?” he’d asked Renjun, and Renjun sputtered and frowned, which was enough of a reaction that it conveyed “yes” back to Doyoung, even though Renjun muttered “I’m 23…” under his breath). The evening office chats then became 8pm, 9pm, then 10pm (before the professor kicked Renjun out) chats in Doyoung’s one-bedroom apartment in a quiet, residential neighborhood two-and-a-half miles north of campus.
When Doyoung asked Renjun why he always insisted that they chat--and oftentimes worked, too, if Renjun didn’t need to be on the lab bench that day--in Doyoung’s apartment, Renjun replied that the temperature regulation in the lab was terrible and the air was too stuffy, and besides, Doyoung would never keep his good brandy in his office. Then, when Doyoung asked him why his apartment rather than any communal meeting space, Renjun replied that the library study rooms were always completely booked way too early in advance and that the common areas were too full of undergrads playing League of Legends. Then, when Doyoung asked him why he insisted on crashing on his couch, Renjun shoved his face further into Doyoung’s couch’s pillow, muffling his voice, and gruffly replied that his roommate had a terrible habit of playing League of Legends until three in the morning and that the guy unfortunately had no conceptual understanding of an “inside voice”.
And then, when Doyoung asked him what in the world he thought he was doing, Renjun stayed silent (really, he doesn't recall what he was thinking he was doing; perhaps it'd been an attempt to shut his professor up, because he was in the middle of quoting a line from the third volume of Das Kapital to Renjun) as he settled his full weight into his professor's lap and gingerly removed the book from his professor's hands, which remained frozen in the air.
It then only took one unrestrained roll of Renjun’s hips into Doyoung’s thighs to unfreeze the professor and catch him up to current events. Ten minutes later and he was taking Renjun hard and fast on the floor, so ruthlessly that Renjun’s hips felt the aftermath for days and traces of the carpet burn on his hands and knees lasted for weeks.
Unfortunately, like any one of the greatest minds of the current generation, Doyoung was a terrifyingly fast learner; so terrifying, in fact, that he learned each and every one of Renjun’s buttons at an anger-inducing (to Renjun, at least) pace.
Three weeks ago, Doyoung was scheduled to guest teach a portion of an undergraduate seminar class, and with that came a series of menial assignments just to make sure some unlucky 19-year-old didn't snooze through the entirety of the talk. Like any good research professor, Doyoung made his grad student grade all the papers, but the caveat for Renjun was that he was forced to grade everything in one sitting while Doyoung read a book off to the side, one hand holding open the paperback and the other one mindlessly fiddling with the remote to the vibrating toy inside of Renjun.
It took Renjun three whole hours on a task that should’ve taken just under one. He’s still apologetic to the two or three students that have a giant blue pen mark going across their assignment, because Doyoung had pressed some button that suddenly made the vibration pattern and intensity change, and even a death grip on the pen couldn’t amend the reactionary jolt of Renjun’s body. By the end of it, Renjun was so sweaty and the muscles in his legs were so exhausted that he could barely ride Doyoung to completion. He’s well aware that the professor could’ve dragged things out even longer if he wanted to, and that constant pressing knowledge elicits such a ball of mixed feelings within him.
“I told you, focus,” Doyoung repeats as his fingers tease at the head of Renjun’s cock. Jesus fuck, Renjun thinks again, narrowly avoiding voicing his thoughts out loud by clamping down his upper teeth on his lower lip. So what if his mental vision wasn't exactly crystal-clear at the moment. Doyoung's hand is obviously distracting, and Renjun is getting increasingly impatient. The fabric of Doyoung’s slacks against the backs of Renjun’s bare thighs are an infuriating barrier to the skin-on-skin contact Renjun craves. But, Renjun would also be lying if he said that his professor could do nothing but unzip the fly of his pants and take his cock out and Renjun wouldn't be reduced to a pantsless, underwearless, stuttering mess. (Yes, it was insanely hot how Doyoung could just casually unzip and leave the rest of himself fully clothed and Renjun would be absolutely powerless to protest Doyoung removing his PhD student’s pants.)
“You didn't normalize the data here before the first PCA. Why?” Doyoung puts his hand over Renjun’s on the mouse and moves the cursor to highlight a block of code on the screen. Renjun grits his teeth. Yeah, fuck him, he forgot about normalization and maybe that was because of a certain someone whose face is hovering over his shoulder as that someone leans forward and adjusts his glasses. “Fix it. You can’t assume all variables are similarly scaled, and PCA isn’t scale-invariant.”
“Yeah, yeah,” Renjun mutters crossly. He lets out a long stream of air as he hovers his index fingers over the F and J keys on the keyboard, attempting to collect his thoughts. How the fuck do you normalize again? Doyoung readjusts his position, briefly leaning to the side to grab a lens cloth off his desk and wipe his glasses. Renjun nearly chokes, because the movement shifts Doyoung’s cock inside him, and Renjun can sense it stiffening again with renewed interest in the current situation. Renjun hears his internal voice yelling at him, having too been interrupted by the professor’s action; Scalar object! Make a scalar object, idiot! he silently screams.
He presses the Enter button twice, then painstakingly types a few lines of code. His eyes briefly scan the new entry for any errors, and when he swears he’s found none, he glances over his shoulder at Doyoung.
“Good, now rerun the whole script from the beginning.”
Renjun swallows, and like any good student, he does as he’s asked. Shift, Enter, Enter, Enter… The blinking cursor moves down the page, and a graph prints out after the final line of code is executed. Renjun stares at it, silent. This is right, right? he thinks to himself. He actually has no clue what the end data is supposed to look like, but nothing in the graph inherently screams “wrong” to him.
Doyoung is silent too, and when Renjun quizzically looks behind him--he regrets it the moment he moves his head, because he has to shift his upper body to get a full look at Doyoung’s facial expression, and that causes Doyoung’s cock to rub inside him--the professor’s eyes are not meeting Renjun’s and instead are dancing over the data points in the graph.
“Hmm,” Doyoung muses, after a few moments of thought. “Do you think the projection of the first PC makes sense given the degree of the polynomial model you picked?”
“Oh come on!” Renjun exclaims, because he’s acutely aware that this is just his professor’s way of torturing him. Doyoung actually doesn’t give a fuck about his answer, he’s just testing Renjun’s mental gymnastics. If anything, it tells Renjun that there is indeed nothing wrong with his end data.
“When I ask you a question, I do expect you to provide an answer, Renjun,” Doyoung states, matter-of-factly. Renjun’s response is silence and a withering stare.
“Fine.” Doyoung sighs, momentarily closing his eyes. “Up. On the desk.”
Renjun swallows thickly. His hands shake as he presses Ctrl+S on the keyboard--god forbid he forget to save his work--and moves the laptop and mouse to the far side of the desk.
Doyoung’s hands are on his hips as they stand up, guiding Renjun and making sure his cock doesn’t slip out. Renjun is nearly on the balls of his feet, chest pressed against thick oak wood and dick sandwiched between his stomach and a piece of paper he prays isn’t some valuable document. He feels Doyoung push up the hem of his shirt until it’s nearly in between his shoulder blades, and one of the professor’s cool and firm hands presses into the small of Renjun’s back, the other one bracing himself against the desk.
Renjun expects to be railed hard like he god-damn deserves, but instead Doyoung is taking his sweet, sweet time, drinking in the sight of the smooth expanse of Renjun’s skin and the shadows cast by his muscles as he arches his back. Doyoung even traces the pad of his thumb over the tight line of Renjun’s rim, shiny with the lube used to open him up earlier, and red with how long it’d spent stretched around the girth of Doyoung’s cock.
“Hurry up,” Renjun wheezes. He wiggles his hips, pushing his ass up as much as he can muster, hoping the show entices Doyoung to get moving.
“Hurry up what?” Doyoung asks with false obliviousness.
Renjun groans. “Come on and just do it.”
“Do what? You need to be more specific, Renjun.”
Again, if Renjun were in any other predicament where he had just a teeny, tiny bit more control over his own body, he might consider turning around and cuffing Doyoung over the ear.
Renjun sighs. “Come on and fuck me, please fuck me, fuck me until I can’t see or think, fuck me until I can taste you in the back of my throat, make me unable to walk for the rest of the week, fuck, please, damn it--” His begging ends in a choke as Doyoung takes not even a full second to pull out and ram back into him, setting forth a punishing pace. The thunk thunk thunk of the desk’s recoil is all Renjun can hear besides his own panting; Doyoung’s upstairs, downstairs, and next door neighbors definitely know exactly what they’re doing. He thinks he could cry, maybe, the drag of Doyoung’s hot and heavy cock inside him causing sparks to fly at the corners of his vision. The asshole professor had kept him touch-starved for the entire day, only allowing him teasing, fleeting touches here and there; for god’s sake, earlier that day Doyoung even made Renjun finger himself open while the professor watched, and the entire ordeal had Renjun threatening to spontaneously combust into flames of embarrassment.
He tries to push his hips back, maybe meet Doyoung partway, but he finds himself near-immobilized by Doyoung’s hand pushing into his back. It’s like he’s nothing but a warm hole for his professor to use, and that thought crossing his mind elicits a full-body tingle. His poor, poor cock is trapped between the combined weight of himself and the professor and the desk, weeping profusely, guaranteeing a puddle of sticky precome smeared all over the wood and some papers; and, oh god, he doesn’t even know if he’s even going to be able to come like this, he can’t even move to touch himself and there’s no way Doyoung would do him that mercy even if he wasn’t pounding Renjun into the desk with the sheer magnitude of force as god intended.
“Is this what you wanted, Renjun?” Doyoung asks, leaning forward until his lips are hovering right over Renjun’s ear.
“Yes, yes, god, yes, so good,” Renjun blubbers, voice hoarse. He feels Doyoung nip at the back of his neck, lips in the shape of a small smile, obviously pleased with the response. The gentle bite turns rough, with Doyoung sinking his teeth in and harshly sucking, relishing in the ever-so-slightly iron-like taste of drawing blood right up to the skin’s surface. Renjun shivers, the thought overcoming him that Doyoung is marking him, claiming him as his, in a spot no one would see unless Renjun turned around, like a not-so-secret secret.
“What a good boy you are,” Doyoung murmurs, and he cards his fingers through Renjun’s hair, before grabbing a fistful to forcefully turn Renjun’s head around to kiss him without restraint.
“Yeah,” Renjun pants out, right into Doyoung’s mouth, eyes half-lidded and only able to see a blurry version of his professor’s infuriatingly handsome face. He’s been on edge for the past several hours, and right now he feels so, so close, body wound tight like a coil, but he still has Doyoung’s full weight immobilizing him. His fingernails must have dug holes into the wood by now, because they don’t know what to do besides hold on for dear life. “‘M a good boy,” he whispers, repeating Doyoung’s words, “just for you.”
“Yes.” Doyoung kisses the shell of his ear. “My good boy.” His voice is low, husky, and oh god does it hit all of Renjun’s buttons all at once, so sudden and overwhelming that before he knows it, he’s coming with a shout, vision going blank as spurts of white gush out of his cock, only to be immediately smeared against the desk as Doyoung fucks him hard and rough through his orgasm.
He’s barely coming down when he hears Doyoung groan harshly, one of the professor’s hands still white-knuckled into Renjun’s back and his bangs tickling the back of Renjun’s neck. It’s not too much longer before Doyoung grunts and his hips stutter, composure finally breaking as he spills into the condom. Renjun is so sensitive, one step away from squealing if he were to take his teeth out of his bottom lip. He braces himself, squeezing his eyes shut, keeping his ass perked up, and waits for Doyoung to slow down.
Doyoung eventually stills, and there’s a several second-long pause where the only sounds in the room are both of them breathing. He carefully pulls out, making sure to disturb Renjun as little as possible, before slumping back in the chair and cautiously tugging the condom off of himself.
“Fuck,” Renjun mutters. He clumsily braces himself against the desk to turn himself around--yes, his legs are momentarily nonfunctional, thank you very much--and barely manages to catch the hem of his shirt from falling down. If it did, it’d likely adhere to his stomach via the come smeared all over him, and that would be mildly upsetting to have to wash out by hand.
“Go get in the shower,” Doyoung says, knotting the condom and unceremoniously tossing it in the wastebasket next to his desk. “I’ll order food first and join you in a minute. What would you like for dinner?”
“Thai, I guess,” Renjun replies. He gingerly takes off his shirt, making sure it doesn’t come in contact with the mess covering his abdomen. “Um, not too spicy this time, though. 2-star, maybe?” He just had his guts rearranged, so maybe his intestines will appreciate taking it light on the capsaicin.
“Sure.” A flicker of a smile passes over Doyoung’s face. It briefly returns as he watches Renjun hobble towards the bathroom. He picks up his phone, and he only needs to go to the next page of his most recent calls to find the phone number of Renjun’s favorite Thai restaurant.
The phone line beeps for twelve seconds before he hears a click and a familiar voice on the other end of the line. For a moment, Doyoung worried that he was calling at an inconvenient time, but he’d glanced at his watch and confirmed that it is currently noon in Seoul. Taeyong should be on his lunch break right now.
“What’s up, man?”
“So you know that PhD student I have that I told you about a while ago?” Doyoung begins.
“Yeah, man! Your first grad student. How’s that going?” Taeyong asks. He sounds excited, which is so typical of him. There is no one else in the world who could be so genuinely excited for Doyoung’s accomplishments and not initially hit him with shock or skepticism. Doyoung can practically see Taeyong now, sitting across the table from him and wolfing down his favorite Chinese takeout for lunch as he blabbers over the phone, an occasional piece of noodle falling from his mouth.
“I fucked him.”
“Dude, what the fuck, you don’t call me for three weeks and then the first time you call it’s on a Monday morning--”
“Afternoon,” Doyoung corrects. Taeyong acts like he didn’t even hear him and just barrels onwards.
“--and you tell me this shit. Genuinely, what the fuck, man? Tell me it was a one-time thing.”
“Well…” Doyoung begins, and he hears Taeyong audibly sigh. “It’s been an eight, nine, maybe ten-time thing…”
“Bro.” There’s a pause of silence, and Doyoung assumes Taeyong is shoving another bite of chow mein into his mouth to give him more resilience to last through the conversation. “Okay, wait. First, you’re calling me from your cell phone, right? Not your office phone?”
“I’m not an idiot,” Doyoung replies.
“Wow, well, I could’ve thought otherwise, ‘cause fucking your student is something only an idiot would do.”
Doyoung winces. He hopes Taeyong is alone in his office right now, because god forbid any of his coworkers overhear his phone conversation; not like it would matter that much, because Doyoung highly doubts any of Taeyong’s coworkers are aware of Doyoung’s existence, but even then, a small inkling of paranoia settles in Doyoung’s gut.
“Doyoung,” Doyoung hears, and Taeyong’s tone is serious; he’s using the kind of voice he only brings out when he has to lay people off, and this is maybe the third time in the entire lifespan of their friendship that Doyoung has been on the receiving end of it. “Don’t forget who you are, where you came from, and what you’ve accomplished. You’ve worked too hard for everything you have just to put it all at risk because of some good dick. Good dick can be found everywhere, but you… your life, your hard work, your blood, sweat, and tears… everything you’ve achieved in your life, 99% of people don’t even have the ability to fathom.”
The silence on the phone line is so thick and pregnant that it’s palpable. Doyoung closes his eyes and lets out a breath he didn’t know he was holding.
“You are correct. Thank you for reminding me, Taeyong.”
“You’re welcome. Now dude, go sit in a corner and do some serious thinking. I gotta get back to work soon, I’m supposed to jump into a meeting in less than ten minutes.”
Doyoung smiles. Taeyong is the only person in his life, besides his mother, who has ever told him to go sit in a corner (after all, everyone else is a little bit too terrified to do that). “Okay. I’ll talk to you later.”
“Talk to you later. Bye, dude.”
The line clicks. Taeyong was the one to hang up. Doyoung sets down his phone and takes off his glasses before rubbing the heels of his palms into his eyes. Taeyong’s words drape uncomfortably over his shoulders, like they're an itchy blanket wrapped around him.
It would be criminal and morally unjust, Doyoung thinks, if he were to reduce Renjun to simply nothing besides “good dick”.