I Never Knew Even Memories Could Get NTR'd?

-Hoo, you've got some pretty decent talent there?

It was back when Kim Cheolsu was still young. Their encounter happened right after he'd first picked up a sword.

-Who are you?

-Me? My name's Kim Taejin.

The woman in hanbok said it with an utterly casual attitude. Looking back now, she had more than enough of a rogue vibe ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠to pass for a common thug. And yet, he couldn't tear his eyes away—probably because it was the first time in his life anyone had ever acknowledged him.

-An aspiring hero, huh? Not bad for a little squirt.

-It doesn't matter. Kids like me, poor as dirt, get left in the dust no matter what. Heroes have to keep getting stronger nonstop. What gear they use, what backing they have, what master they study under... All those factors pile up and create a huge gap.

Cheolsu, an orphan, knew early on that even if he grew strong, he'd top out as a mercenary at best.

-What a cheeky little brat, no fear at all.

-Ow!

Suddenly, he got a knuckle rap on the head. Cheolsu, eyes watering, shot her an indignant glare.

-Why'd you hit me?!

-Seeing a kid with that kind of talent whining like he's dying pisses me off, that's why!

With that, she handed him a single book.

-Wh-what is this?

-Heh heh, it's a sword arts secret manual I developed myself.

He flipped open the book with its crude cover. Unlike the shabby exterior, the contents inside were incredible—even to young Cheolsu. Ways to wield a sword, footwork, how to use strength effectively, and so on. The swordsmanship described was astonishingly detailed. Mastering just what's written here might be enough to become a hero, he thought.

-It's yours now.

-M-me?!

-Eh, I'm not even a sword specialist to begin with, and it's basically a downgraded version of this Cheon-gong Shin-gwon thing I'm researching. But with that alone, you could easily hit B-rank.

A B-rank hero. An impossibly distant realm for the Cheolsu of back then. But with this sword art... maybe it was possible.

-Why give something this precious to me?

-I told you. I don't like seeing a kid blessed with heaven-sent talent moping around like a loser. Consider it an investment in a potential junior who might show up later if opportunity knocks.

With those words, Kim Taejin vanished. It was only later that he learned she was a legendary S-rank hero. But what mattered to Cheolsu wasn't some title. It was the dream that took root in his heart—and the goal of protecting Lee Younghee. Kim Taejin was the one who'd given him those.

He never got another chance to meet her ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠after that. Just a fleeting encounter. She probably didn't even remember him. Still, Cheolsu regarded her as his master in his heart.

'I wonder what Master is up to right now.'

Cheolsu, lost in memories for a moment, opened his eyes. Maybe because of the recent enlightenment he'd gained—old thoughts suddenly resurfaced.

'I've finally made the Cheon-gong Geom my own.'

Train until you drop dead. Easy words to say. But how many could actually do it? How many had shaved off their flesh, shattered their bones, and ground their very souls into the effort?

Even under those brutal conditions, Cheolsu could swear to it: he'd trained until he dropped dead.

'I've honed myself enough to beat that guy from our first spar.'

A week since Kim Yujin vanished. Those days had been meaningful for Cheolsu too. With the guy out of sight, he'd thrown himself solely into training. He was confident his swordsmanship had jumped at least two levels. His skill now was incomparable to before.

'In a way, it's thanks to that bastard.'

The duel promise Yujin had mentioned—the wish granted to the victor. The vague goal of protecting Younghee now felt solidly within reach. Thanks to that, Cheolsu could charge toward it without hesitation.

Of course, he didn't take it at face value. Even if he won and wished for Younghee back, Yujin could just steal her again. Given Younghee's current state, she might even walk back to Yujin on her own. Still, Yujin's proposal had become one possibility for Cheolsu.

"What an idiot."

Lee Younghee, sitting on a bench a short distance away, spoke up. She'd arrived earlier than him and had been waiting.

"Why not give up now and beg for forgiveness? A week's not enough to close that skill gap."

"Why'd you come, then?"

"Yujin told me to watch."

She turned her head away after saying it. Yujin told her to come watch... Probably to show off his power. Either way, it wasn't bad for Cheolsu.

"I didn't wanna watch this lame fight."

"Really? I'm glad—I get to see your face."

Younghee's cheeks flushed red. Seeing that made him chuckle despite himself. No matter their relationship now, just looking at her face gave him strength. It deepened his resolve.

'If I crush him with raw power, even he can't ignore me anymore.'

Cheolsu wasn't without thoughts of his own. He'd looked into Yujin's Heukcheon organization. What he learned: it was a complete demon den.

'Who'd have thought an outfit that worships nothing but strength still existed.'

Heukcheon ran purely on power logic. Even if you were the heir, if they deemed you lacking, no recognition. Coups happened constantly, they said. You had to crush it all to be acknowledged as the true boss.

'Grown up in that environment. In a way, he's purely honest before strength.'

First, show his own power. Bring Younghee back with the wish as promised. Then negotiate from a position of force. The heir's seat was unstable anyway. He wouldn't want to make an enemy of someone who'd beaten him.

'That's what all this training has been for.'

The wooden sword in his grip felt utterly reliable. Cheolsu had feared Yujin. He'd even submitted to him from the heart once. But not anymore.

That guy's provocations, Younghee's pain—they'd forged him into a true swordsman.

'You'll regret raising me, Kim Yujin.'

As he steeled his resolve inwardly—

Thud, thud.

Kim Yujin approached from afar. Maybe because the duel was imminent, but today he looked even bigger.

'No, more than that... his aura feels a bit different...'

As Cheolsu squinted at him—

-Thwack!

Suddenly, Yujin kicked off explosively.

'......Huh?'

An instant—less time than a blink for an ordinary human. Yujin was right in front of him.

'Fast.'

Yujin thrust his fist forward. A terrifying boom echoed. Cheolsu, struck dead-on, flew backward.

"Ch-Cheolsu!"

He barely kept his balance and reset his stance. Somehow, he'd drawn his wooden sword across his chest.

'If I hadn't blocked with the bokken, that would've ended it.'

Even blocking, his wrists trembled. He'd been pushed back a good distance. One blow. And he could feel the guy's full capability.

'This much from pure power and a straight punch...'

Plus that explosive acceleration just now. Cheolsu had figured Yujin was a power-focused type, arrogant enough not to train any proper martial arts. He'd thought technique would let him win.

But this looked more like a martial artist's form.

'Freakin' monster. What the hell did he do in that one week?'

He stared at Yujin standing before him. The guy glared back silently. No usual leisure, no lazy attitude. No inexplicable taunts either. At least, he was facing him as an equal opponent.

Was it weird that this brought relief?

'Calm down. Winning's not impossible.'

Yujin's growth speed was monstrous. But he'd built skill to match. He'd just blocked that sneak attack, hadn't he? Above all, he had the Cheon-gong Geom.

Power aside, his technique was superior.

'No matter how strong the attack, if it doesn't hit, it's meaningless.'

A sensation like facing not a human, but a monster. He gripped the bokken tight. Sharpened his senses.

And moved!

Vanishing from sight in an instant, Cheolsu reappeared behind Yujin.

'Gotcha.'

A perfect blind spot, impossible to predict. He thrust from there.

Or so he thought.

'......Dodged it?'

Yujin evaded it all too easily. As if he'd read every move.

Did his technique surpass even that?

'No way.'

Gnashing his teeth, Cheolsu unleashed his sword arts. The secret techniques from his master's manual.

Every sword technique at his disposal. A frenzy of swordsmanship that would make even seasoned heroes click their tongues in awe—an overwhelming talent with the blade.

'How the...?'

Yet none landed. Yujin dodged or blocked them all, as if he knew every one.

Was this all he amounted to? His—no, his master's sword arts—meaningless to this guy?

'No! Master's Cheon-gong Geom is invincible!'

It was the swordsmanship that brought him this far. He couldn't lose wielding his master's art. If he did, it was his training that fell short.

'Fine, I admit it. Kim Yujin, you're ahead of me even in martial arts.'

It ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠burned, but he had to face it here. His blood, sweat, and tears meant nothing before this arrogant genius.

But he had no intention of ending it like this. Cheolsu went all-in on a desperate gamble.

'At least an arm. That's my pride.'

Gripping the sword ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠two-handed, he gathered mana. A secret technique staking everything on one strike. The Cheon-gong Geom's ultimate move, embodying the user's full power and training.

No matter who Kim Yujin was, he couldn't emerge unscathed from this. At minimum, a wound. Proof he'd fought. A soul-infused strike to leave that mark!

It was blocked by Kim Yujin's first martial technique—like a lie.

'Wha...?'

Even as he flew sideways, Cheolsu bulged his eyes. He knew that technique. Or rather, he knew the "pre-completion" version of it.

His homeroom teacher's words came back late: Details are secret, but Yujin was training under some hero for a bit.

'No way...'

Why... how...

'Why... of all people, you...!'

A fist flew into Cheolsu's face. He tumbled across the ground.