The day he died started like any other kind of failure.
Late again, half soaked in the drizzle that had rolled in over the city, he shoved his way through the bus doors as they hissed shut behind him. The fluorescent lights inside buzzed softly above rows of tired faces. Office workers, students, an old woman gripping a shopping bag that rustled at every bump in the road. Nothing remarkable. Nothing cinematic.
He dropped into an empty seat near the middle, phone still in his hand, the Jujutsu Kaisen opening theme leaking faintly from his earbuds. He had been rewatching the Hidden Inventory arc on his way out the door, eyes glued to the screen instead of the time. Gojo young and laughing, Geto still human and bright beside him. A story he had already consumed, dissected, memorized.
He knew exactly how it all would end. For them. For the world.
For himself, he expected something sparser. A long, unimpressive line that ended in obscurity.
The bus lurched forward. He leaned his head against the cool glass, city lights smearing into streaks of color. A notification popped up on his screen. New analysis video on cursed techniques. He tapped it open without thinking.
Somewhere ahead, tires shrieked.
He did not look up at the sound. The music in his ears drowned out the first honk, the second. It was only when the bus driver cursed aloud, when every head around him snapped toward the windshield, that his eyes finally tore away from the image of Gojo's smirking face.
The truck hurtled toward them, sideways, metal yawing, too close for the mind to process as anything but a wall.
Thoughts exploded in jagged fragments.
No way.
Seriously?
Is this how they always write it?
For a heartbeat he saw himself from outside, like a panel drawn by someone else's hand. Anonymous young man. Background character. No cursed technique, no glowing destiny. Just an ordinary body pinned in an ordinary disaster.
Then the world snapped.
Glass screamed as it shattered. Steel folded like paper. The impact slammed him sideways, ripped the air from his lungs. Pain flared white along his ribs. His phone flew from his hand, the soundtrack cutting out mid-beat.
Weight crushed his chest. A seat. An arm. Someone else's body. Then there was only the roar, the impossible pressure, the copper taste of blood climbing up his throat.
He tried to breathe.
Nothing.
He tried to move.
Nothing.
His field of vision narrowed to a slice of ceiling, hairline cracks spiderwebbing through cheap plastic. In that shrinking tunnel of awareness, one absurd thought rose above the others.
So this is it.
Not eaten by a curse. Not obliterated by a domain expansion. A traffic report and a line on the evening news.
His fingers twitched against the floor. They found nothing. No technique to conjure, no power to call on. Just skin, weak and numb.
The cold that followed the pain felt almost gentle. A tide drawing back.
Darkness poured in from the edges.
As it closed over him, as his heartbeat stuttered and faltered, another thought came, sharp and bitter enough to sting through everything else.
I hate this.
I hate being this weak.
The last sound he heard was not a scream or the groan of collapsing metal. It was the faint, buzzing echo of the song that had cut off.
Then even that faded.
Silence stretched.
For an instant that felt like an eternity, he floated in it. No body. No breath. Only the hollow echo of that resentment, that useless anger at an unfair end.
When sensation returned, it was not gentle.
It was a flood.
Cold air slammed into his lungs like a punch. His back arched against rough sheets. A voice shouted something blurred and distant. Light flared against his eyelids, far too bright.
He gasped, choking on breath and panic, fingers clawing at fabric that was not his.
Pain tore across his skull, a lance driven straight behind his eyes. It brought with it images layered one over another, bleeding into a single, pulsing mass.
Stone paths under bare feet in a walled estate.
The sour smell of old incense.
A man's voice, bored and contemptuous.
"Again. If you cannot sense it by now, perhaps you never will."
He slammed his eyes open.
The ceiling above him was not the cracked plastic of a city bus. It was wooden, polished to a dull sheen, illuminated by the flicker of a hanging lamp. Shadows pooled in the corners of the room, stretched long across papered walls.
He knew this ceiling.
He had seen its twin in manga panels, in frames of an anime that had colored his own dreary life.
No.
The pain surged, and with it more images.
His hands, smaller, pressed flat to a tatami mat, knuckles white with effort.
A boy standing over him, face sharp and familiar in a way that made his stomach twist. Arrogant tilt to the chin, eyes like a knife.
Naoya Zenin.
The name rose unbidden, not from fandom but from memory. The memory of being shoved aside in a corridor for walking too slowly. Of laughter, cool and effortless.
"You really are useless, Ren."
Ren.
The sound of the name in his mind struck like a bell. It did not belong to the man who had died on the bus, but it landed in his chest with the weight of years.
Ren Zenin.
Younger brother. Clan disappointment.
He sucked in another breath, chest heaving. The room wavered, split into double exposure: the wooden ceiling and the crushed bus roof, Naoya's sneer and the reflection in his old phone screen.
"Ren? Ren!"
The shout came from the right. A woman's voice, clipped and anxious. Footsteps thudded on the floor.
He turned his head as if through water.
A woman knelt beside the futon. Her hair was pinned back in a severe knot, streaks of gray at the temples despite a face that was not yet old. The lines at the corners of her mouth deepened as she stared down at him.
Ren's mother.
His new mind supplied the title with a strange, reluctant certainty. Not the woman who had raised his old body. That face was already hazy. But this one came with the weight of countless childhood mornings.
"You hit your head," she said, her tone more annoyed than gentle. "The healer said it was only a minor concussion, but you kept screaming. Can you hear me?"
He could. Every syllable grounded him further in this impossible reality. Her accent, the cadence of her words, the way her eyes flicked over him more in assessment than concern.
"I…" His voice cracked, still raw from a throat that had just been choked by another world's blood. "I hear you."
She exhaled, the tension in her shoulders loosening by a breath.
"Good. You gave everyone enough trouble for one day."
Her gaze lingered on him a heartbeat longer, as if searching for something he had never once managed to show her.
Then she stood, sliding the door aside with a soft rasp.
"I will inform the others you are awake. Rest. Perhaps you can manage not to embarrass the family for at least the rest of the night."
The door clicked shut.
Silence returned, broken only by the faint murmur of distant voices somewhere else in the compound.
He lay there, staring up at that wooden ceiling, heartbeat pounding in his ears.
Bus accident.
Truck.
Pain.
Darkness.
Then this.
He lifted his hand into the lamplight.
The skin was slightly darker than his old one, the fingers longer, callused. A faint scar ran down the back of the right hand, white against tan. He remembered getting it during training, blade skimming too close when his stance slipped.
He had never gotten that scar. Not in his old life.
His fingers trembled.
Ren Zenin.
Reincarnation, some corner of his mind supplied, half hysterical. Like every cheap fanfic he had ever clicked on at three in the morning. Only this time there was no author to blame for the cliché.
A bitter, breathless laugh escaped him, stopping short when his ribs twinged.
"I actually died," he whispered to the ceiling. "And I woke up in Jujutsu Kaisen."
His voice shook on the last three words, caught between awe and nausea.
Fear crawled up from his gut, cold and steady. Because he knew this world. He knew what waited beyond the Zenin estate walls. Special grade curses. Mangled bodies. Smoked ruins where cities once stood.
He also knew what it meant to be a Zenin without a technique.
The memories tangled inside his skull twisted, tightening like a noose. His own life, wasted in quiet frustration, layered over Ren's childhood of contempt.
Weak in one world.
Useless in another.
His hands curled into fists.
Somewhere deep in his chest, under the panic and confusion, something else stirred. It was the same stubborn ember that had burned as the bus crushed him, the one that had refused to accept an anonymous, powerless ending.
If this was a second life, then he would not squander it crawling.
He closed his eyes.
The pain of the merging memories surged one last time, so intense that he thought his skull might split. Images screamed across his mind's eye: Naoya's smirk, the clan head's disinterested gaze, the crushing silence after yet another failed attempt to manifest a technique.
And beneath all of that, grainy anime frames, manga panels, flowcharts he had scribbled on notebook paper mapping out timelines and character fates.
They snapped together.
When the pounding in his temples finally dulled to a throb, his breathing had steadied. Sweat soaked the collar of his sleeping yukata. His heart still raced, but it no longer felt like it would tear itself apart.
He drew in a slow breath and opened his eyes again.
The ceiling waited, unchanged.
This was real.
He was Ren Zenin now.
And in a world where weakness was a death sentence, he had arrived branded as weak.
He stared at his clenched hands until his knuckles went white.
"That's fine," he whispered, voice rough but clear. "I already know how this story goes."
The lamp flickered as if in response.
"I'm not going to die as a background character twice."
## 1.2: Memories of the Zenin Clan and the Weight of Being a Disappointment
Sleep did not come.
Every time he let his eyes slide shut, the two sets of memories clawed for dominance, dragging him backward through years he had lived and years he had only watched.
He gave up on rest and focused instead on sorting.
The Zenin estate unfolded in his mind, room by room. Corridors lined with scrolls, manicured gardens with carefully raked gravel, training grounds stained darker where blood had seeped into the dirt. He remembered running along those paths as a child, trying to match Naoya's longer stride and always failing.
"You're slow, Ren."
He could hear the boy's bored drawl as clearly as if Naoya stood at the foot of his bed.
"And pointless. The clan doesn't need dead weight."
He had been eight, then, lungs burning, legs shaking. He had laughed it off in front of his brother, pretended the words bounced off. Later, alone, he had pressed his fists into his thighs until the nails broke skin, the sting a small, controllable pain compared to the yawning ache of inadequacy.
Those emotions were real. They were not imported from an anime or manga. They were Ren's.
Now they were his as well.
In the dark quiet of his room, he forced himself to follow that thread back further. To the first time his cursed energy had been measured.
A ring of adults around a kneeling child. Their shadows fell long across the floor, faces hidden above the harsh glare of lantern light. The air had tasted dry and sharp, dust stirred by old power.
"Again," someone had ordered.
He had focused, small hands outstretched, trying to do what they had told him to do. To feel the flow that ran under his skin. To shape it into something visible, something worthy.
Nothing had manifested. No inherited technique. No shimmering projection of clan pride.
Just a ripple of raw cursed energy, thick and unfocused, warping the air like heat.
A murmur ran through the onlookers.
"So much waste," one of them muttered.
"An empty vessel," another said.
The words had sunk into his bones.
From that day, every evaluation had been a reminder. Special training sessions had ended early for him. Explanations of advanced techniques skipped over his presence entirely, as if he were furniture instead of family.
At first, he had tried harder. Woken before dawn to practice, stayed out in the training yard until his legs gave out. If effort could bridge the gap, he intended to sprint across it.
Effort alone had not been enough.
The inherited technique never emerged.
The verdict settled over his head like a heavy, invisible mantle.
Disappointment.
He rolled onto his side on the futon, staring at the faint pattern in the tatami. His throat felt tight, his chest hollow.
He had thought, back in his original life, that he understood what it meant to be powerless. To send resumes into a void, to watch opportunities pass him by because he had no connections, no standout talents. To realize that in a world obsessed with success, he was forgettable.
The Zenin clan had refined that sensation into an art.
Here, power was not just money or status. It was literal, tangible. Technique. Lineage. A visible manifestation of worth.
If you lacked it, you were not just unremarkable.
You were defective.
He remembered a family dinner, long table laden with dishes he had not been allowed to touch until the elders had finished. Naoya laughing at some story, gesturing with chopsticks. An older cousin bragging about a newly honed ability. Compliments rippled along the table, voices warm, eyes bright.
Ren had sat in silence, hands folded in his lap, invisible.
At some point, his father had looked his way. The man's expression had not been hostile, exactly. Merely resigned.
"Ren," he had said, not unkindly, not kindly either. "Eat. You will need strength if you are to make anything of yourself at all."
The words could have been encouraging.
They had not been.
He understood, now, with the bitter clarity of his two lives, what had always hung unspoken in the air of this house.
If you are not born with power, you start at a deficit. If you cannot make up for it with something extraordinary, you sink and are forgotten.
Weakness was not a temporary state. It was a sentence.
He sat up slowly, the room spinning once before settling. The headache that had split his skull earlier had dulled to a throbbing reminder of the bus crash and the collision of souls.
He could not afford to drown in self-pity. Not here. Not now.
He had knowledge the old Ren never possessed.
He knew that outside these walls, a blind old monster slept under layers of seals. That an immortal curse would one day stretch its hand over cities. That children yet unborn would grow up only to be devoured in battles no one here could yet imagine.
He also knew that Gojo Satoru, the future strongest, still walked this world as a student, not yet the unshakable pillar he would become. The Hidden Inventory incident had not yet unfolded.
Time.
He had time.
Not much, but more than nothing.
He exhaled slowly, counting the beat of his heart.
First, accept the weight sitting on his shoulders.
He was a Zenin. That came with expectations he had already failed and punishments he already understood too well. It also came with resources. Training grounds. Libraries. Armories.
They had written him off.
Good.
Let them look away.
In his original world, he had cursed the feeling of being overlooked. Here, overlooked could mean freedom to move, to cultivate something outside their narrow definitions of worth.
He sifted through Ren's memories again, this time searching not for moments of humiliation but for cracks in the clan's walls.
Conversations half overheard as servants gossiped in corridors.
Stories of "lesser" techniques, the ones highborn sorcerers scoffed at even as they relied on them for support in battle.
A visiting instructor, mentioned only in passing, who had once offered supplemental training to clan strays with no inherited gifts.
Shadow Style.
The name rose from the back of his mind, linked to images of slender blades and flowing stances. A practical school of swordplay that used cursed energy not for flashy manifestations but for precise reinforcement. And within it, a technique that had stuck in his memory even as a fan.
Simple Domain.
Not a fully realized Domain Expansion with a sure hit ability, but a simplified, flexible barrier technique. A way to claim a small space and enforce your own rules within it. A defensive answer to overwhelming power.
He could see, with the practiced eyes of someone who had spent too many hours analyzing fictional systems, how his current body's "defect" might slot into that path.
No technique.
Excess cursed energy.
Fine.
Pour it into control.
Shape it into space and steel instead of light shows.
The memory of being called "waste" still ached, but now, sitting in the half-lit room, he felt something coiling tight around that pain. A clarity.
They had declared him a disappointment because he did not fit the mold they worshiped.
That did not mean he was empty.
"I won't be what you decided," he said softly to the shadows.
The walls did not answer, but the air felt different. Less suffocating.
The weight of being a disappointment would not vanish. The clan would continue to remind him of it at every opportunity. His brother would still sneer. The elders would still look through him.
He could bear it.
He had borne worse.
The bus crash had taught him exactly how much he hated the taste of helplessness. Now, with that memory fused to Ren's childhood failures, the hatred felt deeper, almost holy.
He would use it.
He let his thoughts move forward along the path he knew he would take.
Shadow Style school.
Leaving the estate in quiet, sanctioned exile to study a "lesser" art. Meeting Kusakabe, who would one day become a dependable, if reluctant, sorcerer of his own. Training until his hands bled and his muscles screamed.
Five years of grinding himself against a whetstone of repetition until his Simple Domain became unshakable.
He could see it as clearly as any future scene from the anime, except this time, the camera sat behind his own eyes.
The weight on his chest did not disappear, but it shifted. From the dead pressure of a verdict to the solid heft of a load he had chosen to carry.
If the Zenin clan insisted on calling him a disappointment, then so be it.
He would make sure the world learned his name for another reason entirely.
## 1.3: Resolve to Learn Shadow Style and Walk the Path of a Sorcerer
Morning seeped into the room as a gray wash of light behind the paper screens. At some point during his long night of sorting and remembering, his body had given in to brief, fitful dozing. Each time he jerked awake, heart hammering, the wooden ceiling was still there, anchoring him in this second life.
By the time footsteps approached his door, his decision had already crystallized.
The sliding panel rasped open without a knock.
An older man in plain robes stepped inside, his presence careful, eyes downcast. A retainer, not blood. Ren's memories provided his name.
Hiro.
"The household has been informed you are awake, young master," Hiro said, bowing. "The clan head has granted you the day to recover. You are not to attend morning drills."
There was a hint of apology in his tone. Morning drills were where worth was displayed. To be excused from them was a reminder, to everyone watching, that you were already counted out.
"I understand," Ren said.
The words felt different in his mouth now. Not the automatic compliance of a beaten child, but a measured acceptance.
Hiro straightened, eyes flicking to his face. Something in Ren's expression must have changed, because the man's brows drew together slightly.
"Should I bring breakfast here?"
"Yes," Ren answered. "Thank you."
Hiro hesitated as if he wanted to say more, then bowed again and retreated.
Ren exhaled slowly, listening to the sounds of the estate filtering through the thin walls. The thud of wooden practice weapons from the training yard. Barked commands. Laughter. Someone crying out in frustration.
He had spent years chasing those sounds, always a half step behind. Today they washed past him like a current that no longer had claim on his direction.
He stood carefully, testing his balance. His legs held. The room tilted once, then steadied.
On the low table by the wall, folded neatly, lay a set of training clothes. His hands moved without conscious thought, pulling on the familiar fabric. The weight of it settled around his shoulders, a reminder of all the mornings he had worn the same uniform and failed to impress anyone in it.
He tied his belt with deliberate care.
One last time, he let his gaze roam over the room. The plain futon. The single chest with his meager personal belongings. The window that looked out onto a strip of garden others would have called beautiful and he had always seen as just another boundary fence.
He stepped closer to the window, sliding it open a fraction.
Cool air brushed his face, carrying the faint scent of earth and pine. Beyond the inner garden walls, the city sprawled in muted colors, and beyond that, somewhere, the larger world that would soon ignite.
He thought of curses bloating in the dark, feeding on human fear. Of children like Yuji, Megumi, Nobara, who would one day bleed for a world that barely knew their names.
He was not naïve enough to think he could save all of them.
He was determined not to be dead weight when the time came to choose whose lives to fight for.
A knock, this time, preceded the door sliding open again. Hiro returned with a tray, the simple breakfast arranged precisely. Rice, miso, pickles, grilled fish.
Ren sat and ate without rush, each bite an anchor. He needed his energy, and not just because his head still ached.
After the meal, he wiped his mouth and set his chopsticks down.
"Hiro," he said.
The retainer straightened, startled by being addressed so directly.
"Yes, young master?"
"There is something I want to ask." Ren met the man's eyes. "About Shadow Style."
The flicker of surprise that crossed Hiro's face confirmed what Ren already knew. In the eyes of the main family, Shadow Style was considered a tool for those who lacked true techniques. A crutch. For a Zenin to show interest in it openly was to admit a certain kind of failure.
"Shadow Style, young master?" Hiro repeated carefully.
"Yes," Ren said. "I heard there is a school that teaches it. Off compound."
Silence stretched between them.
Hiro's gaze flicked to the door, as if expecting someone to be listening.
"There is such a school," he said at last. "It accepts those of minor families and… others. Those without inherited techniques. It is not considered suitable for members of the main line."
"I don't have an inherited technique," Ren said, letting the words sit plain and heavy in the air. "You know that. The entire clan knows that."
Hiro flinched, only slightly.
Ren leaned forward, keeping his voice level.
"They call my cursed energy waste. That does not mean it is useless. Shadow Style uses cursed energy for reinforcement and for barriers, including Simple Domain. I have heard the elders talk about it. They rely on practitioners of it when they need domain countermeasures."
The older man swallowed. For all his deference, he had lived long enough under this roof to understand the politics at play.
"Young master, even if the technique is useful, the clan may not approve of you… aligning yourself with it."
"I am already a disappointment," Ren said, not with self-pity but with a calm that startled even him. "Whether I stay here and swing a sword badly every morning, or go somewhere else and learn to use what I have, their opinion will not improve."
He thought of his father's resigned gaze, his brother's mockery, the elders' indifference.
"I do not intend to remain useless," he continued quietly. "I want to train in Shadow Style. Properly. I want to learn Simple Domain."
Hiro stared at him.
Something in the man's face softened, the careful neutrality cracking just enough to let a sliver of sympathy through.
"I am only a servant," Hiro said. "I cannot grant such permission."
"I know," Ren replied. "But you know the house. You know who to speak to. Who might listen. Who might, at least, carry the request to the clan head without twisting it into something else."
He held the older man's gaze, letting him see the resolve there.
"This is not a whim," Ren said. "I am asking for a chance to make myself useful to the clan and to the Jujutsu world, in the only way I can."
The words were chosen with care. Appeal to duty. To practicality. The Zenin valued strength, but they also valued results. A tool that worked, even if unsightly, was still a tool.
Hiro's shoulders sagged by a fraction.
"I will… see what can be done," he said at last.
He bowed and retreated, leaving Ren alone again.
The wait did not stretch long. Within the hour, a different set of footsteps approached, heavier, more confident. The door slid open to reveal a man in his late forties, hair tied back, expression impassive.
Not the clan head.
But close.
"Ren," the man said. His voice carried the casual weight of someone accustomed to being obeyed. "I hear you have made a request."
Ren bowed from his seated position.
"Yes, uncle."
The man stepped inside, closing the door behind him. He studied Ren with a gaze that felt like cold fingers peeling back skin.
"You wish to attend the Shadow Style school," he said. Not a question.
"Yes," Ren repeated.
"Because you have no inherited technique."
The bluntness stung, but he inclined his head.
"I have no technique," he agreed. "Only cursed energy. More than most, but without proper shape. I believe Shadow Style can give it form. If I can master it, I will not be a burden."
"That remains to be seen," his uncle said. "The clan invests in those who can bring honor and power to the name. You have shown… neither."
Old Ren would have flinched, swallowed back anger and shame.
This Ren let the words pass through him, registering their weight but refusing to carry it.
"I cannot change the past," he said. "I can change what I do from now on. Allow me to train there. If, after a period, I show no improvement, you may cut off support entirely. I will not complain."
His uncle's eyes narrowed, as if trying to detect insolence he could punish.
"And what do you expect to achieve?" the man asked. "With your… limitations."
Ren thought of curses to come, of domains that erased everything inside them. He could not speak of those.
Instead, he spoke of something closer and more acceptable.
"The clan values sorcerers who can stand in battle without needing constant protection," he said. "Simple Domain is a known countermeasure against enemy domains. With my cursed energy reserves, if I learn to construct and maintain stable barriers, I can support others. I can create safe zones. I can keep your more gifted children alive."
The slight stress he put on your was deliberate.
His uncle's mouth twitched. Not quite a smile. Not quite a sneer.
"You would make yourself a shield," he said.
"If that is what is required," Ren answered. "A shield that does not break is worth more than a sword that shatters at the first clash."
Silence fell.
For a moment, Ren wondered if he had pushed too far.
Then his uncle exhaled, the sound edged with something like reluctant amusement.
"You have gained a tongue along with this head injury," he said. "Perhaps it will do you some good."
He turned toward the door.
"I will speak to the clan head," he said. "There is precedent for sending… underperforming children to supplemental schools. It keeps them occupied. Sometimes they even return marginally useful."
He glanced back, eyes hard.
"Do not misunderstand. This is not a reward. If you are granted this, it is because your failures have become tedious. The clan would rather you swing a sword elsewhere than watch you stumble in our yard."
Ren bowed his head.
"I understand."
"See that you do."
The man left.
Ren stayed kneeling longer than protocol required, using the posture to hide the small, fierce smile that tugged at his mouth.
Tedious failure or not, a door had opened.
He rose slowly, moving to the window again. The sky had brightened, clouds thinning to reveal strips of blue.
Shadow Style. Simple Domain. Kusakabe. Five years of hard, honest training far from the suffocating gaze of this house.
Beyond that, Kyoto Jujutsu High, cursed tools reclaimed from the armory, a timeline he already knew beginning to bend under the pressure of his choices.
He pressed his palm flat against the wooden frame.
In his old life, he had watched this world from the outside, powerless to touch it. Now, much as it terrified him, his hands were stained with its weight.
He could run.
Or he could walk the path of a sorcerer, not as a prodigy, not as a destined hero, but as someone who refused to be weak.
"I will learn Shadow Style," he said quietly, as if swearing to the empty garden. "I will master Simple Domain. I will turn this cursed energy you despise into something you cannot ignore."
His reflection in the thin glass of the window looked back at him. Ren Zenin's face, set and steady, eyes darker than they had been yesterday.
He did not look like a disappointment in that moment.
He looked like a boy about to drag himself, step by bloody step, toward a strength no one had ever planned for him to have.
Outside, somewhere beyond the estate walls, curses stirred restlessly in the shadows.
Inside, in a small room that had held more shame than hope for years, a new story began to take shape.
Not the story he had watched.
Not the one the Zenin clan had written for him.
His.
He turned from the window, mind already reaching ahead to the first day at the Shadow Style school, to the feel of a training sword in his hands, to the presence of a quiet boy named Kusakabe at his side.
The path of a sorcerer was paved with exhaustion and pain and the constant risk of death.
He had died once already.
He would not waste the second chance.
Ren Zenin straightened his shoulders, the decision settled in his bones like steel.
Weakness had killed him once.
Now, in this world of curses and techniques, he would dedicate every breath he had left to ensuring it never did so again.