Jujutsu Kaisen: That time a random OP being transfered the soul of a- Chapter 4 4: The System Unveiled

Hi guys, author here! It's a new fanfic, so please share your thoughts in the comnts and reviews.And if you like it, don't forget to drop so stones — they're a great motivator!

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Morning ca too early.

The first rays of dawn crept through the paper screens, bathing Naoya's room in a pale golden glow.

The boy — Naoya — sleeping awkwardly in his futon, was woken by a servant lightly shaking his shoulder."Naoya-sama, it is ti for morning training."

He groaned softly, rolling onto his side. His entire body ached — shoulders, legs, even fingers."Training… more like torture. Every inch of my body hurts," he muttered.

"You are gifted, Naoya-sama. Other people can't even move after their first day of training."

Naoya got to his feet, only to fall face-first because of the soreness in his legs."Ugh… so this is what being gifted feels like. Tastes like blood," he muttered in pain.

"N-Naoya-sama!" the servant called out in panic, preparing for the worst.

"Ugh, just help …" groaned Naoya.

The servant imdiately picked him up, noticing a trickle of blood running from Naoya's nose.The man paled in horror, while Naoya simply wiped it away with his sleeve.

"...Do you think they'll let skip training because of this?" Naoya asked.

The servant remained silent.

Sighing, knowing what the silence ant, Naoya decided to let fate take its course and walked out of his room.

Last night's mory ca flooding back — that brief, shimring flicker of cursed energy dancing across his palms, followed by a floating blue screen that had nearly scared him into passing out.

Had it really happened? Or had exhaustion finally broken his mind?

He rubbed his eyes and muttered half-seriously, "If this is what going insane feels like, it's surprisingly organized."

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By the ti he arrived at the courtyard, the clan's early morning training had already begun. Older Zenin children sparred fiercely, their wooden weapons cracking through the air. To Naoya, it looked less like training and more like a sanctioned brawl.

At the center stood Naobito Zenin — calm and composed, his kimono fluttering lightly in the breeze. His sharp gaze imdiately found Naoya.

"You're late."

"I was ditating," Naoya offered quickly.

"On your futon again?"

"Uh… yes."

A long sigh. "Stand properly."

The boy obeyed, moving beside his father as they began their morning drills. Naobito corrected his stance with sharp taps of a wooden stick, his tone calm but rciless.

"Your feet are uneven. Again.""Your breath is shallow. Again.""Stop thinking and feel it."

Naoya gritted his teeth at his father's complaints.

"Did you make any progress yesterday?" Naobito asked, eyeing his son.

"I got a grasp of it, though it vanished the mont it appeared," Naoya replied.

"Show ."

Naoya nodded, trying to recall the feeling from last night.

Soon, a faint wisp of cursed energy appeared on his palm. The nearby trainees halted, watching the young boy with growing curiosity.

The elders did the sa — so smiling, so frowning — but one thing Naoya could feel clearly was the awe in their eyes.

Naobito smirked at the sight of the wisp and lightly tapped Naoya's hand with his stick.

"Ow!"

And the wisp of cursed energy vanished instantly.

"You lack control," stated Naobito.

"Well, duh," replied Naoya — only to receive a sharp smack on the palm.

"Congratulations, Naoya-sama! Gaining a grasp of cursed energy in just a day — the Zenin clan is sure to flourish!"

"Indeed. Congratulations, clan head," added another elder.

One by one, the instructors and elders began buttering up Naobito.

Naobito, however, rely snorted. "Hmph. Don't inflate his ego. He only just learned manners yesterday. Why are you all lazing around? Get back to training!"

"A little praise wouldn't hurt…" muttered Naoya, earning a glare from his father.

The other instructors and elders quickly scattered, returning to their duties.

Naoya, focused once again, suddenly felt a hand rest gently on his head — it was Naobito, who gave a rare, brief pat.

Widening his eyes, a small smile appeared on Naoya's face.

And the wisp of cursed energy vanished again.

Smack!

"Again," barked Naobito.

"....."

'Who do you think is responsible for losing focus?' Naoya thought bitterly, giving his father a side-eye.

And just like that, the training continued.

"Still too wild," Naobito muttered. "Your control is nonexistent. Breathe deeper. Feel, don't force."

Naoya groaned. "I'm feeling a lot of pain right now. Does that count?"

Naobito's eye twitched. "You talk too much."

Finally, Naobito lowered his stick. "That's enough."

Naoya straightened, panting, sweat running down his temple. "You call that training? I call it… child abuse."

Naobito's brow twitched. "Your mouth moves faster than your technique."

"Then at least I'm good at sothing," Naoya muttered, earning another glare.

Naobito stood over him, arms crossed. "You improved slightly. Slightly."

Naoya cracked an eye open. "So… can I have breakfast now?"

Naobito sighed. "You complain more than you train."

"I call it expressing my suffering creatively."

The faintest ghost of a smirk tugged at Naobito's lips — gone as quickly as it appeared."Get stronger, Naoya."

As his father walked away, Naoya stared up at the blue sky, exhausted but… proud.He had felt it again — that flicker of cursed energy, a bit stronger this ti.

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After the grueling session, Naoya dragged himself back to his room, collapsing face-first onto his futon."Cursed energy," he muttered into the pillow. "More like cursed misery."

Still, curiosity gnawed at him. That strange glowing screen from last night — the one that appeared after he finally managed to summon cursed energy — was it real?

He sat cross-legged, took a deep breath, and whispered,"Alright… if I'm crazy, then let's confirm it."

And as if summoned—

Ding~

The faint ringing echoed again. A translucent blue window shimred into existence before his eyes.

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Na: Naoya Zenin

Title: Body Stealer, Possible Zenin Heir

Cursed Technique: Locked

Cursed Energy: 440 / 450

STR: 10

DEX: 7

VIT: 30

INT: 15

LUK: 10

Extra Points: 0

Achievents: More( )

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Naoya blinked, rubbing his eyes. "Okay… so it wasn't a dream."

He tapped the "Achievents" tab, and another small box unfolded.

_____________________

Achievents:

> Survived 1 year. (1 point) [Collect]

> Had a al. (1 point) [Collect]

> Walking on all fours. (1 point) [Collect]

> Walking on two legs. (1 point) [Collect]

> Running on two legs. (1 point) [Collect]

> Started speaking. (1 point) [Collect]

> Hit soone. (1 point) [Collect]

.

.

.

> Cursed Energy unlocked. (1 point) [Collect]

____________________

"..." Naoya blinked in surprise.

Deciding to test it out, he clicked on one of the Collect buttons.

A soft chi rang again, and "Extra Points" increased from 0 → 1.

Naoya's brows furrowed. "...So it's real. And it gives points for… achievents?"

He looked back at the list and noticed a change.

> Survived 2 years. (1 point) [Collect]

"So it's a progressive achievent," he murmured.

He clicked a few more tis. The soft chi rang again and again, and "Extra Points" rose from 1 → 4.

He leaned back against the wall, thinking. "Is this thing judging my life like a video ga?"

After a long pause, he snorted. "Well, at least soone's keeping track of my suffering."

After fiddling with the system for a while, Naoya gathered a few insights:

1. So achievents had levels — like Age or Walking — with progress bars for the next stage (e.g., walking/running 1 km).

2. It recorded basic milestones too — eating, drinking, speaking — but those had no levels.

3. The points per achievent remained the sa, no matter the level.

After collecting all possible achievents, Naoya glanced at his stat screen again.

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Na: Naoya Zenin

Title: Body Stealer, Possible Zenin Heir

Cursed Technique: Locked

Cursed Energy: 440 / 450

STR: 10

DEX: 7

VIT: 30

INT: 15

LUK: 10

Extra Points: 18

Achievents:

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"Should I use these points now?" muttered Naoya.

After more fiddling he ca to know few more things.

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Na: Naoya Zenin

Title: Body Stealer, Possible Zenin Heir

Cursed Technique: Locked

Cursed Energy: 440 / 450

STR: 15( 5)

DEX: 10( 3)

VIT: 30

INT: 15

LUK: 12( 2)

Extra Points: 8

Achievents:

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There was a 10-point limit on stat upgrades per day. When he tried to add more, the screen flashed red with a ssage:

___________________

Reached Point-up Limit for Today.Ti required to assimilate changes: 23:59 hr

___________________

"

"So I can only add ten points per day," thought Naoya, staring at his hands."Did that work, though? I increased my strength by five points… not much, but still 50% more than before."

He eyed the tatami mats beneath him.

'Do it,' an intrusive thought whispered.

He stared at his fist — then back at the mats.

But before he could act on it, salvation arrived.

"Naoya-sama, breakfast is ready," called the servant from outside.

Imdiately, Naoya's mind shifted tracks. He jumped to his feet.

"Here I co!" he said cheerfully, closing the translucent screen before walking out.