The K-Math Monster
What is the universal image that pops into people's minds abroad when they think of a "Korean"?
K-Pop? Squid Game?
Buldak spicy noodles? Dark gamers?
Or maybe... Kimchi Warrior?
Wrong. All of them.
Well, okay, they aren't entirely wrong.
But still, the absolute first thing that comes to mind when you think of Koreans is...
Without a doubt, that they are "Math Monsters"—!!
(I won't bother mentioning the fact that, despite this, we don't have a single Nobel Prize in the natural sciences.)
Anyway.
I, too, am extremely good at math.
To be precise, it feels like this body's mathematical hardware is abnormally high-spec.
Up until now, I just chalked it up to some generic reincarnation buff. But considering the world I'm in, it seems the author's prejudice-filled setting of "Koreans are unconditionally good at math" was forcefully crammed into this body.
In fact, even in the original manga, Lee Raon was always the science-track genius who, regardless of her other grades, never once lost her spot as the rank-one student in math.
In other words, the current me is a combination of top-tier mathematical hardware and premium software forged in my past life. I am, quite literally, the ultimate lifeform when it comes to math.
If you're wondering why I'm going to such lengths to brag about my math skills...
"Sigh. This is driving me crazy. How does the equation jump like this here?"
"Heh. Foolish mortal. You can solve that in one shot if you use L'Hôpital's rule."
"Ohhh! As expected of Kenji! There was a shortcut like that?!"
Wh-What do you mean, L'Hôpital?!
What on earth are those idiots talking about so proudly—?!
A parade of fools was unfolding right in front of me.
I almost spat out the iced tea I was drinking.
To my eyes, the behavior of Kenji and Suzuki looked something like this, with only a slight exaggeration:
"Let us unleash the power of 'L'Hôpital' and 'Rolle's Theorem' here. We shall annihilate this problem in an instant."
"Hell yeah."
Do these guys think L'Hôpital's rule is some kind of plunger used to unclog a toilet?
Mmmph...!
My mouth was itching like crazy.
I wanted to leap out of my seat this very instant, butt in, and yell, "That's not how you do it!"
L'Hôpital's rule.
It was a method strictly limited to indeterminate forms where both the numerator and denominator approach zero, or both approach infinity.
Yet Suzuki and his buddy were currently slapping derivative symbols onto the numerator and denominator like brainless titans, without even checking the limit conditions first.
Besides, from what I could gather with a quick glance, this wasn't even a problem designed to be solved using L'Hôpital's rule in the first place.
"Whoa~ It's solved! It's solved!"
"Heh, see?"
"This 'L'Hôpital' guy is seriously magical. By the way, is that named after a person?"
"Of course it is. He must have been one smart dude."
You're wrong, you idiots...
Inside my mind, a torrential downpour of tears was already flooding the gates.
Sure, the formula became famous because the French mathematician Guillaume de l'Hôpital published it in his book, but the one who actually proved and created the theorem was Johann Bernoulli!
Ughhh...
A heavy, burning sensation welled up from the depths of my chest.
Specifically, it felt as suffocating as being force-fed a hundred sweet potatoes without a single drop of water.
Unable to take it anymore, my inner personas began whispering in my ears, urging me to stand up right now and stab pieces of chalk straight into their skulls.
First, my inner demon, taking the form of a succubus, spoke up.
Then, the angel with a glowing halo added her two cents, refusing to be outdone.
Wait, is there not a single one of you trying to stop me?!
A miraculous, bipartisan coalition of angel and demon, brought together by L'Hôpital.
Just as my eyes were spinning and my mind was growing faint...
"Hey, you guys."
Shun, who had been quietly watching Kenji and Suzuki's solving process, chimed in with a dubious expression, clicking the back of his mechanical pencil.
"You can't just throw L'Hôpital's rule around without checking the conditions first. Just because the denominator approaches zero doesn't mean the numerator automatically does too. Look, your logic starts falling apart right here."
"But we got the right answer?"
"Then that's just a fluke. Are you going to rely on luck during the actual exam too?"
"Well... no. Then how are we supposed to solve it?"
When Suzuki asked with a pout, Shun let out a soft sigh and pulled the scratch paper toward himself.
"You have to use substitution. Let's set this entire expression as t, and then..."
Scribble, scribble.
The tip of Shun's mechanical pencil glided smoothly across the paper.
His explanation was logical, clean, and free of unnecessary fluff.
Watching him, Kenji and Suzuki let out genuine gasps of admiration. "Ohhh—!"
Oh?
I nibbled on my cheese-loaded doria with a small spoon, casting a sidelong glance at Shun's profile.
Certainly, Ueda Shun was smart.
Unlike the two idiots who were completely lost and barking up the wrong tree, he accurately grasped the essence of the problem and understood exactly what mathematical concept the creator was testing.
Hmph. As expected of a romcom manga's male lead.
Even though he was being teased like a neighborhood punching bag just moments ago—called a "gaze-rapist" and "scum"—seeing his profile as he focused so seriously made me view him in a slightly different light.
He had a solid, athletic build that suggested he was good at sports.
A handsome face, clean-cut enough to earn him the title of ikemen from his best friends.
On top of that, he had the brains to match. Talk about well-rounded, hexagon-tier stats.
I'll give credit where it's due.
Ueda Shun.
Overall, top-tier.
...But.
Chew, chew.
Pulling the spoon from my mouth, I narrowed my eyes.
As I watched Shun fill the scratch paper with his step-by-step solution, a different kind of frustration began to brew inside me.
It's so frustrating. Incredibly frustrating.
The direction of his solution was correct.
But he had absolutely zero tricks up his sleeve.
Should I say his diligent personality was fully reflected in his solving process?
It wasn't that his intuition was lacking or his calculations were slow, but his approach to solving the problem was endlessly straightforward and stubborn.
To put it in perspective, it felt like watching someone stand perfectly still on a completely empty escalator, gripping the handrail tightly and waiting to reach the top instead of just walking up.
It was a level of sluggishness that no Korean could ever tolerate.
Well, still.
"See? If you substitute it like this, the limit ends up being 4... so the answer is option 2. What do you think? The answer is the same as yours, but the process is worlds apart, right?"
"Ah, you're right... It really had absolutely nothing to do with L'Hôpital's rule."
Watching Suzuki and the others nod in meek agreement while Shun spun his mechanical pencil with a grin, the frustration in my chest miraculously began to ease a bit.
Maybe taking it step-by-step like that is the perfect way to explain it to his idiot friends.
Rather than flashy intuition or shortcuts, it was a solid method grounded in the fundamentals that anyone could understand.
That was undoubtedly born from Ueda Shun's characteristic diligence and consideration for others.
I wouldn't call it sophisticated, but I don't dislike that kind of rugged honesty also.
I smiled faintly to myself.
As the study session reached its peak...
The hands of the three boys flipping through the workbook stopped simultaneously, as if by prior agreement.
"...Whoa. This is no joke."
"Is this the boss monster?"
The very last page.
A question designed to filter out the top-tier students for prestigious university admissions—a true separator—revealed its majestic, terrifying form.
Unlike Japan's standardized Center Test, the difficulty of the Main Exams administered directly by prestigious universities like the University of Tokyo or Kyoto University boasted a level of malice that easily rivaled the infamous Killer Questions of the Korean Suneung.
Sure enough, in less than a minute, Suzuki and Kenji declared their surrender and laid down their pencils.
"Ah, this is impossible. It exceeds my brain capacity."
"I don't even have a clue how to approach this..."
While Suzuki and Kenji gave up early and began playing with their drink cups...
"Hmm... If I split the integration interval here... No, the variables don't match..."
Only Shun continued his lonely struggle, his brow slightly furrowed.
Twirl, twirl, twirl.
The silver mechanical pencil spun rapidly between Shun's fingers.
For a long time, Shun wrote down equations and erased them over and over on his scratch paper, but the tangled ball of yarn refused to unravel. It was like wandering through a labyrinth with no exit.
Ah, this is genuinely hard...
"Ugh..."
Finally letting out a groan, Shun tore his eyes away from the workbook and rubbed his face with both hands.
Once he hit a wall, his concentration began to slip, and other thoughts slowly started creeping into his mind.
Then, a sudden realization struck him.
Wait, have the three of us just been talking among ourselves this whole time...?
Shun's gaze drifted cautiously toward the corner of the table.
They had come to Saizeriya together to get closer, but all they had shown her was three guys burying their noses in a math workbook and groaning.
Thinking of Raon, who must have been bored out of her mind playing with her phone all by herself, a wave of guilt washed over Shun.
Should I order some dessert for Raon?
With that thought, Shun casually looked up.
"...Huh?"
For a moment, Shun doubted his own eyes.
Far from being bored, Raon wasn't even looking at her phone. With her hands folded politely over her knees, she was intensely scanning the final page of the workbook Shun had laid open, her eyes darting back and forth.
"Raon?"
When Shun casually called her name...
"Y-Yes?!"
Flinch!
Raon, who had been completely absorbed in the math problem, startled and her delicate shoulders trembled.
Flustered, she opened her large eyes wide and looked back and forth between Shun and Kenji's group across the table.
"Ah, sorry. I didn't mean to startle you."
Shun scratched the back of his head and smiled sheepishly.
"I felt bad because it seemed like we were the only ones talking. You're bored, right? Would you like me to order you some chocolate cake or another dessert?"
"Ah, I'm... I'm fine. I wasn't bored at all..."
"Really? Well, that's a relief."
"It's just..."
"Hmm? Just what?"
Raon, clutching the hem of her skirt tightly, hesitated for a moment.
Her clear eyes wandered through the air before slowly drifting back down to the scratch paper Shun had laid out.
Her lips parted and closed, parting and closing again.
Her small, red lips opened and closed repeatedly as if she were debating something.
In the end, Raon asked very cautiously, her voice soft and timid.
"Um, if... if it's not too rude..."
"Yeah. Go ahead."
"That last question... would it be alright if I tried solving it...?"
With her cheeks slightly flushed, Raon softly added one more thing.
"Because... I think I can solve it."
