"—and that concludes today's lesson. Don't forget the assignment due Monday."
Ren opened his eyes.
For a second, nothing registered. Just a blur of colors—brown desks, white ceiling, sunlight cutting through windows. The droning voice of a teacher somewhere in the background.
Then the headache hit.
It wasn't gradual. One moment there was nothing, and the next his skull was splitting open from the inside. Memories crashed into him like a truck—fragments of a life that wasn't his. A woman cooking breakfast. A man who never smiled. A girl who barely spoke to him. Sixteen years of existence crammed into his brain in the span of three seconds.
Ren gripped the edge of his desk, knuckles white, jaw clenched. A few students glanced his way. He ignored them.
What the hell is this?
The last thing he remembered was falling asleep in his apartment. Twenty-six years old. Dead-end office job. A rerun of some anime playing on his laptop because he was too tired to pick something new.
Now he was sitting in a Japanese high school classroom.
The bell rang. Students around him stood up, gathering bags, chatting about weekend plans. Ren didn't move. His hands were shaking.
Okay. Okay. Think.
He looked down at himself. School uniform—black gakuran with brass buttons. His hands were different. Younger. No calluses, no scars. He touched his face and felt unfamiliar angles.
I'm in someone else's body.
The foreign memories were still settling into place, clicking together like puzzle pieces being forced into slots they didn't quite fit. He had a name now. Ren Kurogami. Second year at Sugisawa Third Municipal High School. Parents dead. Living with relatives who tolerated him at best.
A background character. A nobody.
Sugisawa Third.
The name echoed in his head, and something cold settled in his stomach.
He knew this school.
"Oi, Kurogami. You good?"
Ren looked up. A boy with messy brown hair was standing next to his desk, bag slung over one shoulder. Classmate—the memories supplied a name. Tanaka. They weren't friends, but they'd spoken a few times.
"Fine," Ren said. His voice came out rougher than expected. "Just a headache."
Tanaka shrugged. "You look like shit. Get some sleep, man."
He walked off. Ren watched him go, then turned toward the window.
Outside, the afternoon sun was starting its descent. Orange light spilled across empty sports fields and quiet walkways.
Somewhere in this city, a pink-haired boy with inhuman strength was visiting his dying grandfather.
Somewhere, a girl named Sasaki and a boy named Iguchi were preparing to unseal something they shouldn't.
And somewhere, a jujutsu sorcerer named Megumi Fushiguro was already on his way here, following the trail of a cursed object that would set everything in motion.
Jujutsu Kaisen.
Ren's fingers dug into his palm.
This wasn't just any world. This was that world. The one he'd watched dozens of times. The one where people died brutal deaths and the protagonist's greatest power was his ability to keep getting back up no matter how many times he was broken.
Shibuya. The Culling Game. Sukuna's rampage.
He knew what was coming.
And he was just some random transfer soul in a body that couldn't even see curses.
Perfect.
The classroom had mostly emptied. A few stragglers remained, talking near the door. Ren stood up slowly, testing his balance. The headache was fading, but the disorientation remained—like wearing clothes that didn't quite fit.
He needed information. He needed to figure out exactly what day it was, how much time he had before tonight, and whether he had any way of—
A sound.
Soft. Almost musical.
Then words appeared in his vision.
Not on a screen. Not projected anywhere. Just... there. Floating at the edge of his sight like a translucent notification window.
[SYSTEM BINDING INITIATED]
[Host: Ren Kurogami]
[Soul Origin: Foreign]
[Compatibility: 97.4%]
[Binding Complete]
Ren stared.
The words shifted, rearranging themselves:
[BLADE INHERITANCE SYSTEM - ONLINE]
Through combat and death, inherit the sword styles of legends.
Kill curses. Complete trials. Grow stronger.
Current Sword Styles Unlocked: 0
Cursed Energy Status: DORMANT
A system.
He almost laughed. Of course there was a system. He'd read enough webnovels to know the formula. Transmigrator gets cheat ability, steamrolls through the plot, collects women and power-ups like trading cards.
But standing here, in an empty classroom, knowing what was waiting outside in the dark—
It didn't feel like a cheat.
It felt like being thrown a wooden plank in the middle of the ocean and told to swim to shore.
Another notification:
[INITIAL QUEST]
Quest: First Blood
Objective: Kill one (1) Curse
Reward: [Flowing Water Style] - Basic Sword Form
Time Limit: 24 hours
Failure: Permanent System Deactivation
His eyes locked onto the last line.
Permanent.
If he failed, he'd lose the only advantage he had. He'd be stuck in this world with nothing but borrowed memories and knowledge of a future he couldn't change.
Twenty-four hours.
Tonight, Sasaki and Iguchi would try to unseal Sukuna's finger at school. Curses would be drawn to its presence—weak ones, mostly. Grade 4, maybe Grade 3 at worst. The kind Megumi would dispatch without effort.
But Ren had no cursed energy. Couldn't even see curses yet, according to the system.
How was he supposed to kill something he couldn't perceive?
He looked at the system window again.
Cursed Energy Status: DORMANT
Awakening conditions not met.
That probably meant he needed to encounter a curse firsthand. Experience genuine fear. Maybe nearly die. This world loved using trauma as a power-up mechanic.
Ren exhaled slowly.
The sun was still up. He had time. Maybe five or six hours before things went bad.
He grabbed his bag and walked out of the classroom.
The hallway was mostly empty. His footsteps echoed off the linoleum floor as he made his way toward the stairs.
The borrowed memories guided him on autopilot—turn left here, second staircase on the right, exit through the side door. Ren let the body move while his mind worked.
What do I actually know?
Tonight was the starting point of the entire series. Yuji would eat Sukuna's finger to save his friends. Gojo would show up afterward. Yuji would be taken to Tokyo Jujutsu High, sentenced to death, then given a suspended execution so he could consume the remaining fingers.
That was the canon timeline.
But Ren wasn't Yuji. He wasn't part of the story. Just some nameless student who happened to attend the same school.
If I do nothing, Megumi handles the curses tonight. Yuji eats the finger. Everything proceeds as normal.
That was the safe option. Stay home. Hide under the covers. Let canon play out.
But the system wanted him to kill a curse within twenty-four hours.
And if he failed...
No. I can't afford to lose this.
He reached the shoe lockers near the entrance. Changed into his outdoor shoes mechanically. Stepped outside into the late afternoon light.
The school grounds were quiet. Most students had already left. A few club members lingered on the sports field in the distance.
Ren's gaze drifted toward the main building.
Third floor. East wing.
The Occult Research Club.
That's where Sasaki and Iguchi would be. That's where they kept the finger—sealed inside a box, waiting to be opened by idiots who didn't know any better.
I could go there now. Warn them. Tell them not to open it.
But then what? They'd think he was crazy. Even if they listened, the curses wouldn't just disappear. The finger's presence would keep attracting them.
No. The finger needed to be dealt with properly. By someone who could actually handle it.
Ren turned and started walking toward the school gate.
He needed a weapon.
The walk home took about twenty minutes.
Ren moved through unfamiliar streets, letting muscle memory guide him while he reviewed what he knew about the power system.
Cursed energy came from negative emotions. Fear, anger, hatred, despair. Every human leaked trace amounts of it, which accumulated into curses over time. Sorcerers were those who could control and weaponize that energy.
He currently had none. Or rather, it was "dormant"—which meant the potential existed, but something needed to trigger it.
Probably a life-threatening situation.
Great. Looking forward to it.
The Kurogami residence was a modest two-story house in a quiet neighborhood. Nothing special. A small garden out front, slightly overgrown. The paint on the walls was starting to peel.
Ren let himself in with the key from his bag.
"I'm home."
Silence. The aunt and uncle were probably still at work. The cousin—a girl one year younger than him, according to the memories—was either in her room or out with friends.
Good. He didn't want to explain anything right now.
He went upstairs to his room. Small, plain, barely decorated. A desk cluttered with textbooks he'd never opened. A bed that sagged slightly in the middle. A closet with clothes that didn't fit quite right.
Ren closed the door and sat on the bed.
Okay. Weapon.
He didn't have a sword. Didn't have any martial arts training in this body. The original Ren Kurogami was thoroughly average in every way—no sports, no clubs, no exceptional talents.
But the system promised sword styles. That meant it expected him to use a sword.
Maybe I can find something. A kendo practice sword. A kitchen knife. Anything.
He thought about it for a moment, then got up and searched the closet. Nothing useful. Just clothes and old boxes.
He tried the storage room down the hall. Dusty shelves, forgotten furniture, seasonal decorations. And in the corner—
A wooden bokken.
Old. Worn. Probably belonged to someone who'd long since moved out or passed away. The wood was slightly warped, and the grip was wrapped in faded cloth.
Ren picked it up. Tested its weight.
It wasn't a real sword. Wouldn't cut through anything. But against a curse—
No. Against a curse, this is useless.
Curses couldn't be harmed by normal weapons. Only cursed energy could affect them. That was the fundamental rule of this world.
He needed to awaken his cursed energy first.
Then the system would give him a sword style.
Then maybe—maybe—he could fight.
Ren set the bokken aside and checked the time on his phone.
4:47 PM.
The sun would set around 6:30. Sasaki and Iguchi would probably mess with the finger sometime after dark. Call it 8 or 9 PM.
He had roughly four hours.
Four hours to figure out how to awaken cursed energy, find a weapon that could actually hurt curses, and position himself to kill something without dying in the process.
Easy.
He lay back on the bed and stared at the ceiling.
The system window hovered at the edge of his vision, patient and unmoving.
[Quest: First Blood]
Time Remaining: 23:14:52
Ren closed his eyes.
Tonight, then.
He didn't sleep. Just lay there, running scenarios through his head.
The memories kept settling in, filling gaps he didn't know existed. He remembered the aunt's warm smile when she served dinner. The uncle's clipped tone when he talked about expenses. The cousin's back as she walked away, never quite meeting his eyes.
A lonely existence. No friends. No purpose.
This kid had nothing to live for.
Maybe that's why the transmigration happened. An empty vessel waiting to be filled.
Or maybe it was just random chance. The universe throwing souls around like dice.
Didn't matter. He was here now.
At 6:15, Ren got up. Splashed water on his face. Changed into darker clothes—black hoodie, dark jeans. If he was going to sneak around a school at night, he might as well look the part.
He grabbed the bokken. Useless or not, it was better than nothing.
The aunt called from downstairs. "Ren? Dinner's ready."
"Coming."
He went down and ate mechanically. Rice, grilled fish, miso soup. The aunt chatted about her day. The uncle grunted occasionally. The cousin picked at her food in silence.
A normal family dinner. Completely surreal.
"Going out later," Ren said when he finished. "Meeting a friend."
The aunt looked surprised. The uncle didn't even glance up.
"Don't stay out too late," the aunt said.
"I won't."
By 8 PM, Ren was back at the school.
The gates were locked, but there was a spot along the back wall where the fence had rusted through. He slipped inside without much effort.
The campus was dark. A few security lights cast pools of yellow across the pathways, but most of the buildings were black silhouettes against the night sky.
He made his way toward the main building, keeping to the shadows.
The air felt different now. Heavier. Like something was pressing down on him from all sides. His skin prickled with goosebumps despite the mild temperature.
Curses.
They were already here. He couldn't see them—not yet—but he could feel their presence. An instinctive wrongness that made his hindbrain scream at him to run.
The system window pulsed:
[Cursed Energy Awakening: 12% - Fear Response Detected]
Twelve percent. That was something.
Ren kept walking.
The third floor of the east wing. That's where the Occult Research Club room was. If Sasaki and Iguchi were still following the canon timeline, they'd be there now, messing with the finger like the idiots they were.
And if the curses were attracted to the finger's power—
They'd be heading there too.
He reached the building and slipped through a side entrance. The hallways were pitch black. Emergency exit signs glowed faintly at the corners.
His footsteps sounded too loud.
The pressure intensified with every step. His heart was pounding now—not from exertion, but from something deeper. Something primal.
[Cursed Energy Awakening: 28%]
He climbed the stairs.
Second floor. Third floor.
The door to the east wing hallway stood open.
And beyond it—
Something moved in the darkness.
Ren stopped.
He couldn't see it clearly. Just a shape. A mass of something that didn't belong. It shifted and pulsed like a living shadow, and when it turned—
Eyes.
Dozens of them.
Yellow. Gleaming. Fixed directly on him.
[Cursed Energy Awakening: 67%]
The thing opened what might have been a mouth.
And screamed.