What Matters Is a Heart That Won't Break
"You like fighting, don't you?"
"Haha... a little?"
Kang Han-ul gazed at Kim Seo-yul with a faint smile. The kid kept awkwardly scratching his cheek, yet couldn't hide the pure, unfiltered curiosity in his eyes over Han-ul's every movement. This wasn't some throwaway question tossed out just to keep a conversation alive.
This guy was genuinely, honestly curious. About what that move he'd just used actually was.
This guy's more interesting than I thought.
His natural observational instincts were remarkable on their own. On top of that, he had the kind of easygoing, guileless temperament that made him reach out to a transfer student in trouble. And then there was his pure love of martial arts — and knowledge to match it.
When clueless losers started running their mouths about martial arts like they had earlier, irritation climbed up his spine before he could stop it. But this guy? He actually wanted to answer him. Seriously, properly, about his own technique.
"It's Taekkyeon."
"Taek... kyeon?"
One of his primary martial arts, used countless times even before his reincarnation. In this life, he'd received instruction from his father in everything from Kali Arnis to military combatives, but back in his past life, his father had taught him only two disciplines. Taekwondo — and Taekkyeon.
So what set Taekkyeon apart from Taekwondo? Unorthodox, unpredictable kicks? Some vaguely cringeworthy battle cries? The answer was grappling.
Taekkyeon was a hybrid art whose very purpose centered on toppling your opponent. Within it, grappling stood alongside hand strikes and kicks as one of the core pillars of victory. And among Taekkyeon's signature grappling techniques, there was one in particular.
"The *ttanjuk*."
"...Ttanjuk? As in, tripping someone up?"
"That's the one."
Ttanjuk. In its textbook form, it's a Taekkyeon throwing technique — disrupt the opponent's balance, then hook their ankle, heel, or the back of the knee to collapse their base of support. But the way Han-ul used it was a little different.
He didn't bother actively disrupting his opponent's balance. The moment anyone commits to an attack, their center of gravity shifts — that's simply a law of movement. What he aimed for was that split second. Just before the attack completes, he would deflect or seize the outstretched limb, cutting the motion dead. Then, riding the very momentum the opponent had stepped into themselves, he'd add a slight push of his own and drive them into the ground. Literally throwing a *ttanjuk* into the opponent's own technique.
"If we're being picky, it's not a textbook ttanjuk — it's an original version my dad hacked together himself. No wonder you didn't recognize it."
"Ah! Then, wait — is your father... a Taekkyeon master?"
"Ah, no, nothing like that. He's just a Taekwondo instructor. A perfectly ordinary one."
His father's true identity. It was one of the questions that had gnawed at him constantly since realizing he'd been reborn into this world. Before the reincarnation, his father had been, without question, an ordinary Taekwondo dojang owner. But now? In a great many ways, the man was anything but ordinary.
"I see... That's really, really cool."
Kim Seo-yul, blissfully unaware of any of that undercurrent, simply listened with shining eyes. Han-ul forced a smile and steered the conversation elsewhere.
"You clearly love fighting like crazy. Ever thought about actually training?"
"M-me? Come on, what would someone like me... I just like watching, that's all."
Kim Seo-yul said it sheepishly, rubbing the back of his neck.
"I mean, I've got terrible athletic genes anyway... Starting this late, it'd be pointless."
Kim Seo-yul shook his head hard in denial, but Han-ul could read him clearly. Poor athletic ability. Too late to start. And yet, not once did he say he didn't *want* to. That was not the reaction of someone who genuinely had no interest. The kid was just stacking up excuses to quit before he'd even begun. Han-ul stared at him for a moment, then spoke with a startlingly serious expression.
"Are you an idiot? Why would you give up without even trying—"
"Besides, I have to study."
'!!'
Han-ul's mouth snapped shut. Study. Those two utterly obvious words smacked the back of his head like a baseball bat. The inescapable destiny of every high school student in South Korea. He'd completely forgotten. No — he hadn't even been able to imagine it. Because in his past life as an elite athlete, the word "studying" had never once existed in Kang Han-ul's vocabulary.
But now he was living as the ordinary student he'd always wanted to be. Which meant he had to study. The same coursework his classmates had been grinding through for over a decade — starting from scratch, now, at this age.
"Even so, sometimes I do think I'd like to actually learn fighting myself, at least once—"
"...Damn it. See, someone like me just isn't cut out for it! Starting this late would be pointless anyway!!"
"Wh-whoa, where'd that come from!?"
Kang Han-ul despaired. Even so, the first day of the new semester flowed onward, unremarkable as ever.
"Alright, alright, nice to meet you all. We'll go over the academic calendar now, so listen up."
Being the first day, there were barely any real classes. A parade of unfamiliar teachers filed in each period for introductions, followed by textbook and supply checklists, and long, dreary lectures about performance assessments and grade rankings. Up until now, he could've let it all wash over him — but from here on out, every single word was something he couldn't afford to miss.
Meanwhile, Park Tae-min, who had kicked up a ruckus since that very morning...
"Ugh... son of a bitch, this puts me in a crap mood."
-SLAM!
...stormed out of the classroom mid-way through the very first period. And yet not a single student around him — not even the homeroom teacher who'd walked in — tried to stop him. A perfectly ordinary scene from the world of a School Violence Genre story.
After how much more of that agonizing stretch of time had passed...
"Uuurrrghh...."
The moment final period ended, Kang Han-ul collapsed face-down onto his desk. Who knew that simply sitting upright in a chair all day without a single nap could be this exhausting...? His body clock was hardwired to the setting of 'sleep at school,' so now just staying awake felt like having his soul shaved away layer by layer.
"Han-ul, you heading home?"
"Urrrrrrrrgh...."
"Huh? Why are you so wiped out? You didn't even do anything today."
Pathetic enough that today hadn't even had proper lessons in it. It dawned on him, anew, just how much of school life he'd been skipping out on all in the name of training.
'Well, still.'
Letting out a deep sigh, Han-ul slung his bag over one shoulder. An absolute circus of a first day, sure. But all things considered, it hadn't been half bad. Getting picked at was just par for the course in this world.
"Did you catch the performance assessment schedule and grading criteria?"
"Ha... heard 'em, sure. Too sleepy to remember any of it, though."
"Haha... fair enough. I typed up the schedule, so I'll send it to you on KakaoTalk later."
"You're a lifesaver...."
Either way, he'd made a genuinely good friend. That much counted.
"Whoa, no way — you organized your notes like a computer or something. Are you actually good at studying?"
"Huh? Well... I was first in the whole school last year, I guess."
"What?"
"First in the school... I said."
Han-ul's footsteps stopped dead for a moment.
"Master."
"Wha—!?"
"Please, teach me to study!"
"...I'll just help you. Get up already."
He really was a great guy. His first day as an ordinary high school student. All things considered, hadn't that been a pretty successful day?
Thinking so, Kang Han-ul made his way home. A quiet neighborhood where hardly anyone passed through. And standing in the middle of it, a perfectly ordinary villa apartment that didn't look the least bit special at a glance.
-Beep, beep, beep, beep, chirr-click~
Punching in the code at the entrance and stepping inside, he was greeted by a scenery as tediously familiar as his past life itself. Up the stairs, turn his head just slightly, open the door to Unit 403 — and there it was, home. The door lock code was his parents' wedding anniversary. Almost everything matched his past life exactly... but there were things that had changed too.
-Sllurp, chomp chomp chomp
Stepping into the apartment, he spotted a boy tearing into well-fermented kimchi with his bare hands. Jet-black hair and dark eyes. Clean, elegant features, and an impression so serene it bordered on chilling. Han-ul tossed his backpack onto the sofa and asked the boy, utterly casual.
"Hey, Jin. Where'd Mom and Dad go?"
The boy, fully immersed in his meal, lifted his head slightly to answer.
"The Master and the Madam went on their honeymoon."
"...They've been married twenty years?"
"They said it was a honeymoon."
"Ah... right, sure."
Han-ul chose his words carefully. One of the biggest changes since his reincarnation into this world was the sudden proliferation of foreign acquaintances around his father who hadn't existed before. And this guy was the closest of the lot to their family.
His name was Yatsuka Jin. Japanese, apparently. The story was that trouble had arisen within his clan, and Jin's late father entrusted him to this family. From around the time elementary school started, they'd grown up as practically brothers, and now Jin had rented the apartment right next door — they lived almost as one household.
"How was school? Weren't you looking forward to it."
The boy asked in his usual glacial tone as he piled the neatly torn kimchi onto his rice. Han-ul stripped off his uniform at his bedroom door and answered lazily.
"Eh... not bad, all things considered. Someone picked a fight with me, which was a pain, but..."
"Ohh. A brawl on your first day?"
"No, not an actual fight..."
"True. Children playing house couldn't hope to see through your skill."
-Gulp gulp gulp, CLANG!
The kid downed an entire bowl of soybean paste stew like it was makgeolli, then picked up the wooden practice sword lying beside him and rose from his seat.
"So. Who do I need to kill?"
"...Huh?"
"Who's the target? If they're enough to annoy you, the Three Major Alliances? Let me sweep the rabble away entirely while I'm at it, and place all of Seoul in the palm of your—"
"Are you insane!? What are you, yakuza!? Someone gave me a hard time and you want to KILL them!?"
"............"
A brief silence. Jin stood there with his practice sword, mulling something over with great deliberation, then answered.
".....Probably?"
"Probably, my ass. Finish eating and do the dishes, you brat."
Jin set the sword down with a look of profound disappointment. Then he stacked his emptied dishes and carried them to the sink, dutifully starting the washing up, before opening his mouth once more.
"Then if you weren't fighting, what exactly did you do all day? Don't tell me you actually sat through class."
"Hey, what's a student supposed to do if not attend class?"
"A waste of time. At least, for you."
Brushing aside everything Han-ul had poured into today without a second's hesitation, the boy pressed on, relentless.
"You've spent your whole life brawling, and now you want to pick up a pencil and study? You could debut as a Taekwondo athlete tomorrow and take gold. Start boxing or UFC, and money ordinary people couldn't earn in a lifetime would land straight in your account. And in that position, you want to study... Even stupidity has its limits."
"........."
-SHHHHHHHH!
The stream of water bursting from the faucet slammed mercilessly against the surface of the dishes.
"More than anything, your essence is not that of an ordinary man."
Craving the fight. Savoring the fight. Taking genuine joy in watching himself grow stronger through the process. A born warrior, through and through.
"Born a dragon, why would you crawl into the dirt and play at being an earthworm? Keep scavenging through the mud like an ordinary man and you'll lose your mind first. No — before you ever reach that point, someone else will drag you out of the dirt by force. Live as quietly as you like; in the end, you'll walk the road that was always yours."
-Click.
The torrent of water cut off. Han-ul watched Jin set the last dish onto the drying rack, then opened his mouth, a bitter taste in it.
"I know."
He knew that, in the end, brawling was what he was built for. That studying didn't suit his nature, and starting now would be far too late. That an ordinary school life was a suit of clothes that would never fit him.
He knew. He knew all of it, damn it.
"And still... it's the one chance in a lifetime to try living like everyone else."
Two lives, granted like a miracle. Wasn't it fair to spend one of them wearing ill-fitting clothes? To make some stupid mistakes for once? He'd barely paused to breathe across most of his lives — it had been nothing but training, all the way down.
"Besides, how does it make any sense that I got to this age without a single real friend!? If I don't make friends now, I'm gonna spend the rest of my life doing nothing but brawl!!"
"That's a hurtful thing to say."
"You're not a friend, you're family!"
"True enough."
Jin nodded, satisfied. But then something seemed to occur to him — he crossed his arms and spoke again.
"Still, 'struggling from a lack of friendships' doesn't quite hold up. Didn't you have a girlfriend and get along just fine? That German girl with the enormous chest..."
"Clara's our parents' friends' daughter, that's the only reason we hung out! I told you, it was never like that!"
The moment his ex-(sort of?)-girlfriend — the one he desperately wanted to forget — entered the conversation, Han-ul outright convulsed in denial. But in the face of that reaction, Jin merely tilted his head, puzzled, and added:
"Didn't that girl kiss you, though?"
"...That was an accident."
"She was rolling her tongue around in there."
"Shut up."
It was summer.