Chapter Text
The morning sun filtered through the blinds of Room 307 in the Computer Science building, casting light stripes across Sunoo's sleeping face. He'd dozed off at his desk again, his cheek pressed against his notebook where he'd been sketching flowcharts for his algorithm until 3 AM. A half-eaten triangle kimbap from the convenience store lay forgotten beside his keyboard, evidence of another skipped proper meal.
"Yah! Kim Sunoo!"
The sharp voice jolted him awake. Sunoo's round glasses were askew on his face as he blinked rapidly, trying to orient himself. Jay stood in the doorway, wearing a leather jacket despite the warm September weather, his dyed blonde hair styled perfectly despite the early hour.
"You slept here again?" Jay walked over, picking up empty bubble tea cups with exaggerated dismay. "This is getting ridiculous. You have a perfectly good bed in our apartment."
"I was making progress," Sunoo mumbled, stretching his arms above his head. His back cracked in protest. "The emotional variance calculations were finally making sense around midnight."
"You know what else makes sense? Sleep. In a bed. Like a normal person." Jay dropped his bag on a nearby chair and started organizing Sunoo's scattered papers. It was a familiar routine - Jay cleaning up after Sunoo's coding marathons, pretending to be annoyed but unable to hide his concern.
Sunoo checked his phone. 8:47 AM. "Don't you have Advanced Electronics with Professor Kim right now?"
"Skipped it." Jay shrugged at Sunoo's disapproving look. "Someone had to make sure you didn't miss your thesis meeting. Again."
Sunoo's eyes widened. "That's today?"
"In exactly..." Jay checked his watch, "thirteen minutes. With Professor Park. Who specifically said, and I quote, 'If Mr. Kim misses another meeting, his funding might need to be reevaluated.'"
"Why didn't you wake me earlier?" Sunoo scrambled to gather his materials, nearly knocking over his cold coffee in the process. His presentation wasn't ready - he'd meant to polish it last night before he got distracted by that bug in the compatibility matrix...
Jay watched with amusement as Sunoo stuffed papers into his messenger bag, muttering under his breath about regression analyses and correlation coefficients. "You know, most people have normal crisis moments in college. Like failing a test or getting drunk at a party. You're the only person I know who has breakdowns about algorithmic love predictions."
"It's not about love predictions," Sunoo protested, running his fingers through his dark hair in a futile attempt to look presentable. "It's about understanding the patterns in successful relationships and creating a mathematical model to—"
"—to help people find love," Jay finished. "Which would be more convincing if you'd ever actually been in love yourself."
Sunoo ignored him, too busy checking his laptop's battery life. Twelve minutes to find Professor Park and convince her that his thesis wasn't a complete disaster. He could do this. Probably.
"Your shirt's inside out, by the way," Jay called as Sunoo rushed past him.
Sunoo skidded to a halt in the hallway, looking down at his wrinkled button-up. Great. Professional presentation: zero, sleep deprivation: one.
The Computer Science building was already buzzing with activity. Students clustered around the bulletin boards where the Innovation Challenge teams would be posted later that week. Sunoo hurried past them, dodging a group of freshmen who were arguing about JavaScript frameworks.
He nearly collided with Ni-ki, the programming prodigy freshman who somehow had already earned a reputation for hacking the university's grading system "just to see if he could." The younger student was typing on his phone while walking, probably coding even between classes.
"Hyung!" Ni-ki caught Sunoo's arm to steady him. "Are you okay? You look..."
"Like death warmed over?" Sunoo suggested, still speed-walking toward Professor Park's office.
"I was going to say 'passionate about your work' but yeah, that too." Ni-ki fell into step beside him. "Did you figure out the emotional variance bug?"
"Almost. The problem is the self-reported data sets. People lie about their feelings, or they don't understand them, or they—" Sunoo stopped abruptly. "Wait, how do you know about that?"
Ni-ki grinned sheepishly. "I might have looked at your repository last night. Your commit messages get really interesting at 2 AM. Lots of keyboard smashing and existential questions about love."
"You hacked my private repository?"
"'Hacked' is such a strong word. I prefer 'showed academic interest in a senior's research.'" Ni-ki's phone buzzed. "Oh, Jake's having a party tonight. Are you coming?"
"Can't. Working."
"You always say that." Ni-ki's dark eyes studied him thoughtfully. "You know, for someone writing a dating algorithm, you don't do much dating."
"Not you too," Sunoo groaned. "I already get enough of that from Jay."
They reached Professor Park's office just as Jungwon, the student council president, was leaving it. He was dressed impeccably as always, his silver name badge gleaming on his blazer.
"Sunoo! Perfect timing." Jungwon's bright smile didn't quite hide his concern. "Professor Park was just asking about you. Something about missed meetings?"
Sunoo checked his phone. Two minutes late. Not terrible, considering.
"Thanks, Jungwon. Ni-ki, I'll look at those commit comments later." He straightened his inside-out shirt, took a deep breath, and knocked on Professor Park's door.
"Come in, Mr. Kim." Professor Park's voice was crisp. "I trust you have progress to report?"
The next forty-five minutes were a blur of technical questions, progress reports, and barely concealed skepticism. Professor Park, a brilliant computer scientist who specialized in artificial intelligence, didn't seem entirely convinced that love could be reduced to algorithms.
"Your technical approach is sound," she said, reviewing his latest data models. "But relationships aren't just about compatibility metrics. There's an inherent chaos to human emotion that resists quantification."
"That's why I'm incorporating psychological profiles and behavioral analysis," Sunoo explained, pulling up his flowcharts. "By cross-referencing multiple data points, we can identify patterns that—"
"Theory is one thing, Mr. Kim. But have you tested this with real users?"
Sunoo hesitated. "I'm still in the development phase..."
"Science requires real-world validation." Professor Park leaned back in her chair. "Your funding committee meeting is in three weeks. I suggest you find a way to demonstrate practical applications before then."
Sunoo left her office feeling drained. The morning sun had given way to clouds, matching his mood. He had three weeks to prove that his algorithm could predict real relationships, but where was he going to find test subjects willing to...
His phone buzzed. A message from Jay: "Don't forget to eat lunch! Also, I did something you'll thank me for later. 😈"
Sunoo was too tired to decode Jay's cryptic messages. He headed to the computer lab, his sanctuary of logic and predictability. No emotions to quantify there, just pure code.
The computer lab was quiet at midday, sunlight streaming through the tall windows and catching dust motes in its beams. Sunoo claimed his usual spot in the corner, surrounded by the gentle hum of machines. He'd barely opened his laptop when Sunghoon appeared, carrying two cups of boba from the campus café.
"You look terrible," Sunghoon said by way of greeting, placing one cup in front of Sunoo. "How'd the meeting go?"
"Thanks for the confidence boost." Sunoo took a grateful sip. "Professor Park wants real-world test data in three weeks."
"Ah." Sunghoon pulled up a chair, his perfect posture a stark contrast to Sunoo's slouch. "That explains why Jay's been running around like a mad scientist all morning."
"What do you mean?"
"Nothing." Sunghoon's poker face was impressive, but the slight twitch of his lips betrayed amusement. "Just... check your email sometime today."
Before Sunoo could interrogate him further, the lab door opened again. A tall figure in a leather jacket paused in the doorway, silhouetted against the hallway lights. For a moment, Sunoo's breath caught - something about the stranger's presence commanded attention. Then the figure stepped forward, and Sunoo realized it was just Jake, probably looking for Sunghoon.
"There you are," Jake said to Sunghoon. "We need you at the Innovation Challenge meeting. Also," he turned to Sunoo with a grin, "Jay says to stop ignoring his messages."
"I'm not ignoring them, I'm strategically avoiding potential chaos." But Sunoo pulled out his phone anyway. Twenty-three messages from Jay, all with varying degrees of exclamation points.
"The party tonight," Jake continued, leaning against a desk. "You're coming, right? Heesung's going to perform."
"Heeseung?" The name was vaguely familiar.
"Robotics major, plays guitar, probably the only person as dedicated to his work as you are to yours." Jake's casual tone didn't quite hide his matchmaking intentions. "He's been working on this amazing project with AI-integrated prosthetics..."
"Not interested," Sunoo said automatically, though something tugged at his memory. A robotics student who combined technology with art? That sounded like...
"Your loss," Jake shrugged. "Though you might change your mind when you see—"
"Jake," Sunghoon interrupted smoothly, standing up. "The meeting?"
As they left, Sunoo could hear them arguing in the hallway about party preparations and something about a "perfect plan." He chose to ignore it, focusing instead on his code. The emotional variance calculations still weren't working properly. How could he quantify something as abstract as chemistry between people?
The afternoon slipped away as Sunoo lost himself in programming. He barely noticed when other students filtered in and out of the lab, or when the sunlight faded to evening shadows. His world narrowed to lines of code and cups of bubble tea, each algorithm iteration getting closer to... something. He wasn't sure what anymore.
At some point, Ni-ki dropped by with a sandwich and a lecture about proper nutrition. "Hyung, you can't live on caffeine and sugar."
"Watch me," Sunoo muttered, but he ate the sandwich anyway.
The lab gradually emptied as evening approached. Snippets of conversation floated through the open door - excitement about Jake's party, speculation about the Innovation Challenge teams, debates about the latest tech trends. Normal college life, happening somewhere beyond Sunoo's bubble of algorithms and artificial intelligence.
It was nearly 9 PM when his phone buzzed again, this time with Jay's familiar grinning face on the screen. Sunoo almost didn't answer - he was finally making progress with a new compatibility matrix - but something in him needed a break from the endless code.
"What is it this time?" he asked, putting the phone on speaker.
What followed would change everything - though Sunoo didn't know it yet. Jay's revelation about the HeartCode profile, Sunghoon's knowing comments, the mysterious RoboticRebel who would crash his perfectly ordered world...
The party at Jake's apartment was in full swing, music pulsing through the converted industrial space that had become the unofficial hangout for their friend group. Fairy lights strung across exposed brick walls cast a warm glow over the crowd of students. In one corner, Heesung sat on a worn leather couch, absently strumming his guitar while watching his friends' attempts at karaoke.
"You're brooding again," Jake said, dropping onto the couch beside him. "It's my party, you're not allowed to brood."
"I'm not brooding," Heeseung protested, though he knew his tendency to get lost in thought often came across that way. "Just thinking about the prosthetics project."
"Liar. You're thinking about that cute guy from the coffee shop again."
Heeseung's fingers slipped on the guitar strings. Last week, he'd been getting his morning coffee when someone had crashed into him, spilling papers everywhere. He'd helped gather them up - complex flowcharts and algorithms he'd only caught glimpses of - and handed them back to a flustered boy with round glasses and the softest-looking hair he'd ever seen. He'd meant to introduce himself properly, but the boy had practically run away, leaving behind only the lingering scent of vanilla and the memory of surprised eyes.
"I told you," Jake continued, "he's in Computer Science. I could easily—"
"Don't." Heeseung set his guitar aside. "No matchmaking."
"Fine, but at least check your phone. That dating app you downloaded has been buzzing all evening."
Heeseung had almost forgotten about HeartCode. He'd created a profile on impulse last week, after another late night in the robotics lab left him questioning if there was more to life than circuit boards and coding. He hadn't expected much from it - most people didn't understand his passion for combining technology with art, his desire to make machines that could help people connect rather than just compute.
Across the room, Ni-ki was showing Jungwon something on his phone, both of them glancing occasionally in Heeseung's direction with poorly concealed grins. That was never a good sign.
"Oh god," Jake suddenly said, staring at his own phone. "Jay actually did it."
"Did what?"
"Nothing! Nothing at all. Totally unrelated, but you should definitely check HeartCode right now."
Before Heeseung could question further, someone called for him to perform. He'd promised Jake he'd play a few songs, part of their ongoing effort to make him "less mysterious" to their classmates. If they only knew how much he rambled when he was excited about a project...
Back in the computer lab, Sunoo was having a crisis.
"'Cute computer science major seeking his perfect match. Loves bubble tea, coding until sunrise, and collecting Ryan plushies'?" he read aloud, his voice rising with each word. "Jay!"
The profile Jay had created was mortifyingly accurate. The photos weren't just good - they captured moments Sunoo didn't even remember: laughing with friends, focused on his work, even one of him asleep in the lab surrounded by his beloved plushies. He looked... real. Not the carefully controlled image he usually presented to the world.
"The plushies thing is true!" Jay defended. "And I made sure to check the 'interested in men' box, so you're welcome."
"You can't just out people on dating apps!"
"Please, the whole department knew you were gay when you spent an entire AI Ethics lecture designing a program to analyze the correlation between hand gestures and sexuality, using K-pop boy groups as your data set."
Sunoo felt his face burn. That had been for research purposes only. Mostly.
"Besides," Jay continued, his voice softening, "you're not in high school anymore. No one here cares who you like. They're more concerned about your unhealthy relationship with caffeine and your apparent desire to marry your laptop."
In the background of Jay's call, music swelled. A guitar began playing, followed by a voice that made Sunoo's hand pause over the keyboard. Deep, gentle, with an emotional rawness that cut through all his carefully constructed defenses.
"Who's that?" he asked, trying to sound casual.
"That would be Heeseung. The one Jake's been trying to introduce you to for months? You'd know him if you ever left the lab."
Sunoo minimized his error logs, drawn despite himself to the HeartCode tab. The mysterious RoboticRebel's profile called to him, promising something his algorithms couldn't predict.
"Fine," Sunoo said finally, staring at his screens. "I'll look at some profiles. But only for research purposes."
"Sure, sure. Research." Jay's grin was audible. "Start with RoboticRebel. Trust me on this one."
The guitar music in the background had shifted to something softer, more intimate. Sunoo found himself typing to its rhythm as he navigated HeartCode's interface. The site was well-designed, he noted professionally - clean architecture, intuitive user flow, elegant data visualization of compatibility metrics...
He was stalling.
"Stop analyzing the UX design and search for RoboticRebel already," Jay demanded. "I can hear you thinking about code optimization."
"I'm not—" Sunoo started, then stopped as the profile loaded.
Dark eyes stared back at him from the screen, intense and thoughtful. The first photo showed RoboticRebel in what looked like a robotics workshop, surrounded by half-finished projects and scattered components. He was wearing a black t-shirt that showed off toned arms, focused completely on something just out of frame. The concentration in his expression was oddly familiar.
The next photo caught Sunoo's breath. RoboticRebel on stage, head bowed over a guitar, light catching the sharp line of his jaw. The same voice Sunoo had heard through Jay's phone? The timing couldn't be coincidence.
But it was the last photo that made his heart stutter. RoboticRebel laughing, caught in a candid moment, all that intensity transformed into pure joy. Something about the genuine emotion in that image made all of Sunoo's careful algorithms feel suddenly inadequate.
"His bio," Jay prompted when Sunoo had been silent too long. "Read his bio."
"Building robots by day, making music by night," Sunoo read aloud. "Looking for someone who sees the art in algorithms and the poetry in programming." His voice caught on the last words. "That's... actually kind of beautiful."
At Jake's party, Heesung had just finished his set when his phone buzzed. He stepped away from the makeshift stage, nodding thanks to the scattered applause. Playing music always left him feeling exposed, like he'd shared something too personal with strangers. But tonight felt different, more purposeful, as if he'd been playing for someone specific even if they weren't there.
Finding a quiet corner, he checked the HeartCode notification. His breath caught.
The profile photo showed a boy with round glasses and an embarrassed smile, hugging a Ryan plushie. More photos followed: the same boy laughing in a noraebang, sunlight catching his dark hair; focused at a laptop in a coffee shop, fingers flying over keys; sleeping peacefully in what looked like a computer lab, surrounded by empty bubble tea cups and scattered papers.
Heeseung's heart stopped. He knew those papers. He'd helped pick them up last week, catching glimpses of complex algorithms about... relationship predictions?
"Jake," he called out, voice urgent. "The guy from the coffee shop. He's in Computer Science, right?"
Jake appeared beside him, grinning far too knowingly. "Kim Sunoo. Senior. Working on some crazy AI project about love or something. Why?"
But Heeseung was already reading the profile bio: "Dedicated Computer Science major seeking connection beyond binary. Creator of relationship prediction algorithms, collector of Ryan plushies, and firm believer that love might be the one thing that can't be computed. Looking for someone who understands that technology isn't just about logic - it's about making the world a little less lonely."
The words resonated with something deep in Heesung's core. All his life, he'd struggled to explain why he combined robotics with music, why he believed technology could be both precise and poetic. And here was someone who seemed to understand, even if he approached it from the opposite direction.
Back in the computer lab, Sunoo's finger hovered over the "Like" button. Just for research, he told himself. To test the algorithm. To gather data.
To lie to himself one more time.
He clicked.
Instantly, his thesis project exploded with error messages. Red warnings flooded his screen as his carefully crafted algorithm tried to process RoboticRebel's profile. The compatibility calculations were failing, spinning out impossible results and contradictory predictions.
"No, no, no," Sunoo muttered, fingers flying over the keyboard. This couldn't be happening. He'd tested the code a thousand times. It was supposed to handle any possible combination of traits and preferences. Unless...
Unless it had encountered something it couldn't quantify. Something that defied its basic assumptions about how attraction worked.
The HeartCode notification popped up: "It's a match!"
Sunoo stared at his screens - the failing algorithm and the successful match side by side. Years of research, countless hours of coding, all his theories about predicting love... and here was something that broke every rule he'd written.
Across campus, Heesung looked at the matching notification and smiled. He should have known the universe wouldn't let their coffee shop encounter be their only meeting. Some things couldn't be calculated or predicted. Some things just had to happen.
"Hey," Jake called from across the room. "Innovation Challenge teams just posted online!"
Heeseung checked the university portal, scrolling through partner assignments. His eyes widened.
Partner: Kim Sunoo (Computer Science)
Project Category: AI Applications in Social Connection
Due Date: End of Semester
In the computer lab, Sunoo was still trying to debug his crashing program when the same notification arrived. He looked at his new project partner's name, then at the HeartCode match still glowing on his screen, and finally at the Ryan plushie watching him with its knowing smile.
"Don't say it," he told the plushie.