I stared blankly into the mirror for maybe two seconds after realizing I’d come back.

Then my breath suddenly caught. My chest tightened, and I started breathing fast.

It wasn’t because the room lacked air, and it wasn’t some regression side effect either.

‘Then that means... outside right now...’

I turned my head and stared at the doorknob on my tightly shut bedroom door.

On the other side, I could feel two presences I missed so much it hurt.

“Honey. Should we go in?”

“Just leave him. He needs time to pull himself together.”

“It’s been a whole week like this!”

“Shh. He’ll hear you. You know how hard this has been on Muhyuk, so don’t say that.”

“I’m just scared he’ll do something stupid. You heard him muttering to himself just now...”

The moment I heard my parents’ voices, fidgeting outside the door—

something started dripping out of tear ducts I’d thought were dried up a long time ago.

I pushed myself up from the bed and staggered toward the door.

My parents were right outside.

Alive. Safe. Exactly as I remembered them the last time I ever saw them.

“...”

I wiped my face hard with the back of my hand and stood there taking deep breaths over and over.

The hand on the doorknob wouldn’t stop shaking.

I was terrified that the second I stepped out, all of this would turn out to be a dream.

Creeeak...

So I opened the door very slowly, like nothing was wrong. Like it was the most natural thing in the world.

“...Mom. Dad.”

Both of them froze and stared at me like I’d just risen from the dead.

I mean, yeah, their son who’d been locked up for days suddenly walked out with a puffy face, so of course they were shocked.

But me?

This wasn’t “a few days.” This was twenty years.

“Uh—hey! Muhyuk! What’s wrong?!”

“Do you need something? Want Mom to get it for you?”

I could feel how scared they were that I’d bolt back into my room.

In that tiny moment, a thousand words jammed up in my throat.

I missed you. I love you. I swear I won’t ever make you suffer because of me again. Thank you for showing up in front of me again—

I swallowed all of it.

And I said the one thing I needed most right now.

“I’m... hungry. Let’s eat.”

The way it came out—like a kid whining—made my parents go blank for a beat.

“...Huh?”

“What?”

First an awkward smile. Then a visible release of tension. And finally, just like I’d planned, a baffled laugh.

“We were about to eat anyway. Perfect timing. Just wait a sec!”

“Don’t go back to your room. Sit at the table. I’ll get it ready fast.”

I watched them rush to the kitchen, almost tripping over each other.

Seeing them bicker while cooking together made a stupid little laugh slip out of me.

“Heh... hahahaha...”

“Is he losing it because he’s hungry?”

“I’ll bring out some cherry tomatoes—eat those first!”

That day, the second I regressed, I got my biggest wish back.

****

For the first few days after coming back, I did absolutely nothing productive.

I clung to my parents like I’d turned back into an elementary school kid.

“...What’s gotten into you, seriously?”

“Are you sure you’re my son? The one who was crying and saying his life was over?”

Yeah, yeah, just let me be gross for a while. It’s been twenty years for me, okay?

They were confused at first, but I could tell how relieved they were to see me brighter again.

“Dad. Wanna play games together? I’ve forgotten everything because it’s been so long, but...”

“Are you laying groundwork to ask for something?”

After work, the Kim household’s head would end up glued to a console with his son until late at night, then get smacked on the back by Mom.

“Mom, look. Stretch like this. If you half-ass it, it doesn’t do anything.”

“Ugh, I don’t wanna...”

My mom had been on the judo team back in the day, but after marriage she’d become the world champion of not moving. Still, she started exercising because I dragged her into it. She complained a few times—like she genuinely hated me for it—but if it was about our family’s health, I wasn’t backing down.

I guess my parents decided, “That constitution test really shocked him hard.”

...Maybe that was true back then.

But right now I just wanted them healthy and happy for a long, long time.

‘From here on, I’m starting over.’

Every time we sat together eating, I made a quiet vow to treasure and protect this miracle of a second chance.

“Okay, Mom, Dad, have a good day at work.”

“Don’t just stay home all day. Go out, meet some friends too.”

“Yeah, yeah. Be careful.”

Both of my parents worked, so from the moment they left until they got back, I was alone.

That was when I calmly watched the changes inside my body.

This young, solid body felt like it could do anything.

Compared to the wreck I’d dragged around before I regressed, it was honestly like heaven and earth.

‘Gotta treat it right.’

Back then, I thought training was simple: more, harder, always.

But that wasn’t true.

When you’re young you can force things and survive. Then it stacks. And one day your body just breaks.

I learned that the hard way after twenty years as a vagabond in the underworld.

‘This time, no rushing. I’m building my body properly.’

I already had a clear picture of how I needed to train, and what direction to take.

After loosening up lightly in the living room, I sat down cross-legged.

I breathed in slowly.

Something stirred in my lower belly.

Inside me...

there was a dantian.

I’d checked it dozens of times since the night I regressed, and still, every time I felt it, my mouth curved up without permission.

‘I can feel it for real.’

I wasn’t constitution-incompatible anymore.

Qi flowed smoothly in my body, and at its center was a dantian.

Right now it felt smaller than a bean, but instinct told me it could grow far bigger.

I’d need a real constitution test to know my exact grade... but even if I was below Level 7, it didn’t matter.

A real dantian wasn’t even comparable to an artificial one.

—Even if you go back, will you still learn martial arts?

When Dr. Man asked me that, I said yes.

I meant it.

Even if I got reborn, I wanted to learn martial arts and be a martial artist.

“...A real martial artist.”

Not some underworld vagabond scraping by day to day.

A martial artist who could stand in the open, on the righteous path.

From here on, I could change the future.

And I had to.

So I started laying out everything I needed to do.

Any major events I remembered, I wrote down the second they resurfaced.

People I wanted to see again. People I was grateful to.

And pests who’d be better for the world if I killed them early.

I kept writing, building my plan piece by piece.

Near the end, I wrote four words and stared at them for a while.

“Heavenly Demon Cult....”

About twenty years from now, they would launch terrorist attacks on the entire world.

They’d raid governments, occupy them by force, and some countries would actually fall under their rule.

The chaos, fear, and body count would be unreal.

“This time, I’m not letting that happen.”

Before I regressed, I didn’t care if the world ended.

My body was dying anyway, and I had no family or friends left to protect.

But now?

Now I had my family with me.

A healthy body.

A future that was wide open.

‘There’s no way a world run by a brain-dead cult stays normal.’

The Heavenly Demon Cult was a demonic, brutal group that didn’t care what methods it used to get stronger.

A future where they thrived was a nightmare.

Under the law of “only strength matters,” common sense and public safety got crushed, and the cultists ran around committing disgusting crimes.

And for a while, no one had been able to punish them.

‘Back then, after I lost my parents and was dying alone, I didn’t care about any of that... but not anymore.’

I decided I was going to stop the Heavenly Demon Cult as much as I possibly could.

I tapped the notebook full of messy plans and thought it through.

I had a lot written down.

But what I actually needed to do was simple.

“Get stronger. Stronger than anyone.”

I lifted my head and looked at the poster on the living room wall.

—Anyone dissatisfied with my rule, come here. If you’re qualified, I’ll accept your duel.

The most decorated champion in World Martial Arts Tournament history.

And the man who would later be revealed as the Heavenly Demon Cult Leader.

Richard Han.

The martial artist I’d respected more than anyone stared down at me from the poster.

“So if I beat you, you’ll quit wasting your life on this cult crap, right?”

The man who would one day be my finals opponent at the World Martial Arts Tournament just smiled back with absolute confidence.

****

My birthday always landed during summer break.

This year, the moment I turned nineteen, I went to a specialized hospital with my heart pounding and got my constitution evaluated.

...Then I got slapped with a constitution-incompatible verdict and spent a while losing my mind and rotting in my room—

but this time I snapped out of it fast enough that I still had vacation days left.

Which meant, yeah.

I was a high school senior right now.

For most people, this was the age where you studied like your life depended on it.

But for someone whose career path was “martial artist,” that didn’t apply.

“Still looks the same.”

I pulled a cap low over my face and headed to Namdaemun Market.

Walking familiar streets, I drifted into memories and glanced around.

Even on a weekday, plenty of people. Packed storefronts.

But the deeper I went into the back side of the underground arcades—places normal foot traffic didn’t touch—the quieter it got.

Every now and then I felt a nasty gaze from the shadows.

‘Drug-soaked vagabonds.’

The faint smell of chemicals mixed with rot. The stink of a street I’d lived in for decades dragged my emotions down automatically.

I clicked my tongue and ignored their eyes as I walked to my destination.

A little later, I stopped in front of a building with no sign.

Inside was maybe... what, 150 square feet?

A rusty iron door, plastered with talismans, made it look even more ominous.

I was used to it, so I stepped up without hesitation and pounded on the thick door.

BANGBANGBANGBANG—!

Loud heavy metal music was blasting inside.

If I didn’t knock that hard, the person in there wouldn’t even notice someone showed up.

After a moment, the music cut off.

A wary woman’s voice came from inside.

“...Who is it?”

Creeeak.

The door opened a crack—barely enough to fit a hand through.

A bunch of chains and locks dangled inside as extra security.

Through that gap I saw red-dyed hair.

I looked lower and met the eyes of a woman in heavy makeup and a rider jacket, glaring up at me.

Trying not to laugh, I said,

“This the place that does qi procedures?”

“...A customer?”

The face I’d wanted to see again glared at me with total annoyance, then shook her head.

“Not working hours. What do you want, showing up at the ass-crack of dawn?”

For the record, it was past 3 p.m.

I stared at her—way younger than in my memories—with a dead-tired look.

—The dantian settled nicely. In a day or two you’ll feel a heavy energy in your lower belly.

This was the very same quack who’d illegally implanted my artificial dantian in my first life.

The benefactor who’d given one-eyed me my first job afterward, and helped me out in a dozen other ways.

“...I heard you’re really good, so I came a long way to talk. How about we drink some tea and chat?”

I smiled politely and tried to sound gentle.

She reacted like I’d shown her a bug, hardened her face, and started to slam the door.

“Get lost. I’m not interested.”

Wait—wait, hold on.

I shot my hand forward and shoved it into the narrowing gap.

“Just talk to me for a second.”

“You gonna move that or what? You want me to saw it off?”

She wasn’t bluffing.

From inside, she grabbed a saw and lifted it like she meant business.

...Okay. Something about this first meeting was already off.

But I didn’t have a choice.

I had to say something that would hook her.

“Kim Bokja. Let’s talk.”

“Y-you—who the hell are you?!”

The instant I said her real name—one almost nobody knew—Kim Bokja’s face went bright red.