Chapter 5. Discipline (2)
Whether he knew it or not, Professor Seo Sang-wook began the lecture right away, drawing all the attention solely to Lee Dojin rather than himself.
"Ahem... We'll continue from page 74 where we left off last time. It's March 16th today, so let's read one page each starting from problem 19. Stop at page 95."
3 plus 16 equals 19. It was his own logical choice, but none of the students cared. They were just trying their best to cram the incomprehensible strings of sentences from the textbook into their heads. After all, everyone had already drawn their conclusions based on the shock from the previous class.
Professor Seo Sang-wook's teaching style was utterly unhelpful... but to better understand Lee Dojin's upcoming lecture, it was still best to pay close attention.
Lee Sea was no exception, though she couldn't help the sleepiness creeping in more and more.
What the hell is this even saying...
She'd tried flipping through the book at home once and had immediately given up, convinced she wouldn't understand it on her own. Her preview attempt had failed spectacularly, forcing her to close the book after less than a minute.
...Is this really stuff high schoolers are supposed to read?
It was all about controlling and absorbing external mana, written in Korean characters but feeling like some alien language. This dragged on as the students took turns reading the textbook aloud, until Professor Seo Sang-wook launched his sleep-inducing "explanation" assault.
The classroom atmosphere, nearly wiped out, completely transformed from that point on.
"Alright, that's the progress for today... For the remaining time, Teacher Lee Dojin will assist with the practical session."
Clap clap clap clap—! Thunderous applause erupted without anyone prompting it. A fervent cheer blending anticipation and relief. Professor Seo Sang-wook looked pleased, seemingly indifferent to the complete reversal of power dynamics or the class itself, while Lee Dojin stepped forward to the podium, showing a faint hint of joy with just a subtle smile.
Suddenly, Lee Sea overheard the girls whispering among themselves.
"Seriously, he's so handsome it's speechless... His fashion is insane too, just perfect from head to toe. How much older is he than us?"
"Twenty-five, right...? Seven years?"
"That's not that much..."
From her seat in the very back row, Lee Sea rolled her eyes at the absurd conversation drifting over unbidden.
Are they out of their minds?
Seven years might sound small, but that meant at least seven to eight thousand more bowls of rice. And they were clearly divided into adult and minor—how could they spout such nonsense? Sure, she admitted he was handsome and dressed sharply outside, but at home, he wore stretched-out T-shirts around the neck and shorts year-round except in the dead of winter. She wondered if they'd still hold onto their delusions after witnessing that intimate reality.
Lee Dojin picked up the microphone.
"Did everyone have a good weekend?"
"Yes—!"
He grinned at the cheerful response, then followed up almost like a warning.
"Today's content might be a bit tough... Think you can keep up?"
"Yes—!"
The reply came back even more enthusiastic than before. Lee Dojin smiled again and lightly waved his hand.
Shoooo—
A mana construct materialized in the air. Different from last class in both the color of light it emitted and its shape—like the center of a large rug had been pressed down, slightly distorted yet forming a three-dimensional rectangle.
"Last time, we learned about the construct that dissipates the recoil energy when internal mana is emitted. You all remember, right? Today, we'll cover the opposite: how to control external mana energy when it's transmitted to you. In short, most of the defense magic you know and use is based on this construct's principles. Got it?"
"...But why didn't Sang-wook explain it like that? No cap, if I just recorded myself reading the book and played it, I'd teach better than him without putting anyone to sleep."
Jin Yu-ri shot back at Yoo Hae-bin's baffled mutter from the left.
"The professor said exactly that. Anyone who wasn't paying attention wouldn't get it."
"Hah, funny. So if you could only take one class between Sang-wook and Dojin-ssi, who would it be?"
"...Dojin-ssi?"
Lee Sea quietly retorted, glaring, and Yoo Hae-bin panicked, scrambling for an excuse after her careless rambling.
"Huh? No, I misspoke. Dojin-hyung."
"...Dojin-hyung?"
"I mean, uh... Professor Lee Dojin."
"If you wanna chat, go outside. You're distracting from the lecture."
Jin Yu-ri wasn't scolding them for no reason. The most crucial explanation of the class was underway.
"There are three main categories: repulsion, trajectory correction, and absorption. Repulsion covers general shield magic, trajectory correction is for ranged interference types, and a prime example of absorption is..."
Lee Dojin swung his hand wide. A hemispherical barrier rippled into existence around him, and the students gasped in shock.
High-level magic that any Jeil High second-year had likely seen somewhere at least once.
"Grade 3 magic 'Barrier'. A technique that lets you utilize a portion of the opponent's emitted mana for yourself. The difference depends on the construct's completion and the caster's mana control and purity, but done right, it can reduce damage from most magic—regardless of type—to near zero. For instance, the late Jeong Se-bin, honorary professor at Jeil University, once said... all existing defense magic is either a derivative of Barrier or another form of it."
A heavy silence descended on the lecture hall. Lee Dojin's expression remained stoic as he mentioned "Jeong Se-bin," but everyone present knew he was her son.
Breaking the hush was Professor Seo Sang-wook, skimming papers in the corner.
"Hold on, Dojin. Did Teacher Jeong Se-bin really hold that view? It's the first I've heard of it. As you know, there are systematic differences."
"She told me that when I first learned Barrier. She mentioned writing a paper on it... I remember that much."
It was an answer to the question, but Professor Seo Sang-wook focused on what it implied.
"When you first learned Barrier... That means over ten years ago..."
"Yes, about then."
Murmurs rippled through the students.
"Middle school and already learning Barrier? No way."
"Psh, why lie to show off here?"
"Wait, that actually makes sense."
"Guess the rumors of him being a total genius back then are true."
In the lecture hall filled with awe toward Lee Dojin, only Lee Sea bowed her head. It was something she'd never even dreamed of. Conversations between her faintly remembered parents and her genius brother—shared by just the three of them. What else had there been? Probably so much. Some of it surely about her. She was part of the family of four, but she'd been too young—the only one too young. Too young to fully understand and accept their kind explanations, and before she could grow, her parents were gone.
Then she felt eyes on her. Jin Yu-ri from the next seat was looking at her with an inscrutable gaze, and Lee Sea tried to remind herself.
...It's just paranoia.
Don't overthink it. Don't get upset or overreact without hearing it directly. She wouldn't tolerate it if she did hear it, but until then, don't show it. Her brother was at school now too.
"Ahem, alright. Dojin, come to my lab after class. Continue the lecture."
Professor Seo Sang-wook, lost in scholarly passion, finally remembered it was class time. Lee Dojin pressed on with the explanation, and soon it was time for the students' practicals. Much like last class—decent but with rough edges. But after Lee Dojin's pointers, they showed marked improvement.
As he strolled casually through the lecture hall, Lee Dojin reached the leftmost back row.
He spoke in a meaningful tone.
"Yoo Hae-bin, Lee Sea, Jin Yu-ri. You three, one by one. I'll give you thirty seconds—discuss among yourselves or steal ideas from your neighbors if you want. Detecting what your opponent has done is crucial for defense constructs."
"I'll just go."
Jin Yu-ri replied swiftly. Shaaa... Just like Lee Dojin's demo—a rug-like construct with a depressed center. He examined it briefly before pointing out improvements.
"The connection between the edges and absorption area is a bit weak. Don't think of making them separately and merging—imagine pressing down the center of a flat tetrahedron with mana. It'll be better."
"......"
Jin Yu-ri stared up at Lee Dojin in a daze, eyes full of wonder at how he'd spotted that.
Next was Yoo Hae-bin.
"Oh... Looks pretty good to me."
"Yoo Hae-bin, great sense. Well done."
"Psh, gotta be at least this good. Thanks!"
Jin Yu-ri's expression soured slightly. She hated to admit it, but it was better than hers.
Finally, the last one.
"Um... Lee Sea?"
A hint of hesitation crept into Lee Dojin's otherwise steady voice. Lee Sea took it as doubt about her ability and steeled herself to show him, drawing out her mana.
And his evaluation followed.
Clap clap clap. He clapped lightly, his tone excited.
"Great job—really great. No flaws, best completion of any construct today."
It was near-high praise, but Lee Sea felt doubt over joy. Really? Was he just praising his little sister? But upon closer inspection, it seemed genuine.
"Whoa, oh..."
"......"
Yoo Hae-bin's admiration and Jin Yu-ri's subtly trembling eyes confirmed it—her result was solid.
As the beaming Lee Dojin turned away,
"Professor?"
"Yes, Jin Yu-ri?"
Jin Yu-ri halted him with a challenging tone.
"Last class, I asked if I could get my construct re-evaluated... Is that possible?"
She glanced slyly at Lee Sea. Only then did Lee Sea realize why the front-row ghost had moved here.
To compare.
Since she'd gotten an evaluation from Lee Dojin too. Planning to highlight the clear difference right beside her.
The other students were already watching with interest.
Lee Dojin sighed wordlessly, asking with his eyes: Okay?
Lee Sea raised both hands in response.
"Then Jin Yu-ri and Lee Sea, both at once. I'll tell you what's improved since last class and what still needs work."
"Yes, Professor."
"...Yes."
Sitting side by side, Jin Yu-ri and Lee Sea exchanged glances. And the next moment—
Swooo... Paang!
A quiet sound from Lee Sea's side. In contrast, Jin Yu-ri summoned hers with force.
The lecture hall fell utterly silent, and Lee Dojin spoke lowly.
"Jin Yu-ri, well done. You've fixed almost everything I pointed out last week."
"...Thank you."
She had every reason to gloat, but her voice was subdued. And Lee Sea read unmistakable joy in her brother's gaze.
"Lee Sea... If this were a test and I were grading, you'd get full marks."
Not just as a professor, but as a brother—clear pride shining through. Lee Sea etched it into her heart, her mood matching his gaze exactly.
Right now, I was barely holding back the urge to hum a tune.
After finishing the critiques, I returned to the front and looked over the whole room. Everyone did well, worked hard... but the one who stood out most was, of course, Sea. I shouldn't play favorites, and I won't deny I do, but it's a plain fact my sister did the best.
Her expression looked so much brighter than when she entered. I'd been worried since she insisted on practicing alone, but our Sea pulls through. So proud and gratifying.
Composing my pleased feelings, I checked my watch: 2:50 PM. Ten minutes left. I could wrap up... but since my sister nailed it, time for big bro to show off too.
"Then one more thing before we end today's class."
I'd gotten Professor Seo Sang-wook's permission beforehand. A little show would motivate the kids... though he clearly planned to do nothing himself. Fine by me; it's easier that way.
Tak.
With the students watching, I snapped my fingers once. A translucent barrier formed in a 1-meter radius around me, visualizing even the central construct.
"I'll demonstrate how the construct moves under external impact in barrier magic. One volunteer up front to cast an attack spell. Anyone want to try?"
The moment I finished, over half the students shot their hands up.