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2026-06-07
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2026-06-07
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Jujutsu Kaisen: Paired Falling Stars

Summary:

The black flash is an interesting phenomenon. A critical hit based mainly on luck. Something so decisive in battle yet so unpredictable.

This story explores what could've happened if the one blessed by the black sparks lost their favor in the wrong moment.

Notes:

(See the end of the work for notes.)

Chapter 1: Transfiguration

Chapter Text

Tokyo Jujutsu Metropolitan Curse Technical College

Incident Report – Shibuya Incident

Date: October 31st, 2018

Subject: Act of Jujutsu Terrorism centered around the Shibuya Crossing, Tokyo

Issuing Authority: Jujutsu Society Headquarters

Incident Summary:

On October 31st, a major Jujutsu terrorist attack was orchestrated by curse user Suguru Geto and associating parties in the Shibuya district of Tokyo. The incident resulted in mass civilian casualties and the death of multiple Grade 1 sorcerers, as well as the sealing of Satoru Gojo and the full manifestation of Ryomen Sukuna. A full damage assessment is ongoing.

Rulings:

1. Special Grade curse user Suguru Geto is confirmed alive and sentenced to be immediately executed should the chance present itself.

2. Satoru Gojo is to be permanently exiled from Jujutsu society due to his involvement in the Shibuya incident. Any attempts to unseal him will warrant punishment.

3. Masamichi Yaga is sentenced to death for his connection to Suguru Geto and Satoru Gojo as an inciter of the Shibuya incident.

4. Yuji Itadori’s status is to be investigated. The suspension of his execution order is to be re-evaluated accordingly after the investigation has concluded.

5. Atsuya Kusakabe is appointed as the investigator of Yuji Itadori’s current state.

Additional Notes:

All sorcerers are advised to treat any confirmed sighting of Yuji Itadori as a special grade level threat until further notice.

 

—————Shibuya, October 31st, 11:31 PM —————

 

Domain Expansion: Self-Embodiment of Perfection

Yuji’s eyes shot wide open.

His opponent was maniacally cackling at him, his mouth wide open to reveal four small arms with their fingers intertwined in a pair of handsigns that Yuji was all-too familiar with.

He hadn’t thought that Mahito would resort to a drastic measure such as this. The last time he had caught Yuji in his domain expansion, it had almost resulted in the cursed spirit’s death. Sukuna didn’t take kindly to outsiders touching his soul. He had made that rather clear by tearing a huge gash through Mahito’s shoulder back then.

There was no time to think about any of that right now. The barren, gray wasteland around them was already starting to shift. Yuji noticed massive hands appearing behind Mahito, as a dangerous purple tint filled the area around the three of them.

Finally, his eyes locked onto the enemy. Yuji’s legs strained, preparing to carry him over to his target as fast as possible. Without lifting his eyes from humanity’s curse, Yuji dashed forth.

Behind him, Aoi Todo had finally reacted as well. A circle of blue light, shining bright like the reflection of the moon in the sea, started to expand.

New Shadow Style: Simple Domain

An anti-domain technique, as Yuji knew. He was momentarily relieved to know that Aoi would be protected from the domain expansion for now.

Yuji was certain that Mahito would be unable to use Idle Transfiguration on Yuji’s own soul anyways, but it was a different story with the Grade 1 sorcerer beside him.

His sprint continued, kicking up dust from the rocky, barren ground that had once been part of a sprawling city.

The rocky, barren ground…

Why is the ground still the same?

Mahito was still cackling right in front of him, but why were there no hands anymore? What happened to the purple light of Self-Embodiment of Perfection?

The sound of a fleshy explosion broke through Yuji’s train of thought.

“Aoi!”, he screamed, turning his head to his brother. At the current moment, Aoi was missing his left hand. In the air, there was a clump of flesh that exploded into numerous tiny spikes, reminding Yuji of the attacks that the blood manipulator had used against him earlier.

Before Yuji had even turned back to face Mahito, the curse had already passed him.

Yuji could only watch, as his enemy rushed toward his brother in a relentless charge, planting his fist firmly into Aoi’s abdomen and, to Yuji’s horror, landing a devastating

“BLACK FLASH!”

Mahito jumped back. The gorilla was, surprisingly enough, still standing. It seemed that he had concentrated all of his cursed energy into his abdomen to guard against the cursed spirit's attack. Though it had seemingly only worked to a certain point, evidenced by the swath of blood Todo had spat out.

Whatever, he’d just kill him with the next one, then.

Mahito coalesced his dark purple cursed energy over his fists once more, as he once again sprinted in Aoi’s direction. But right as he was about to reach him, something caught his eye.

A pendant?

That little metal thing that the gorilla always wore around his neck. It hit the ground right in front of Todo, revealing… pictures of Itadori and some random woman?

For just a split second, Mahito’s attention was diverted from the enemy right in front of him.

Enough time for Aoi. A grin spread over the gorilla’s face. The blood and bruises all over his body, his missing hand and his discolored abdomen, none of it mattered in this moment, as he knew exactly what he had to do. His remaining hand moved fast as a bolt of lightning as his palm hit the vaguely outstretched palm of Mahito, and a clapping sound echoed through the battlefield.

Black Flash

Yuji’s fist hit Mahito’s left cheek with what felt like the force of a thousand strikes. The sparks of black echoed throughout the battlefield, dancing around the crater of destruction that Ryomen Sukuna had previously carved into the face of the earth using Yuji’s own hands.

Bearing the brunt of that black flash was the worst thing that could’ve happened now! Even on the brink of death, that gorilla is still as annoying as ever, Mahito grinned. The blood all over his face didn’t matter to him. He could repair the physical damage easily and keep fighting unhindered. Regardless, it doesn’t matter. I have finally realized it! The true shape of my soul!

“Idle Transfiguration”

Mahito’s body began to distort and bend, bursting out in all directions and expanding rapidly. Yuji stopped in his tracks in shock, just to see thousands of eyes stare back at him, each of them vanishing quickly just for a new one to appear. In its place. Teeth sprouted on the weird blob that was Mahito, and stitches could be seen slowly wrapping themselves around the weird orb of flesh.

For a moment, it reminded Yuji of a cursed womb.

The stitches started ripping apart violently, starting from the top of the cocoon of flesh. After only a second that still felt endlessly long to Yuji, Mahito’s humanoid form came into view again.

Instant Spirit Body of Distorted Killing

He looked different. Mahito was no longer covered in stitches like previously. His body looked like it was made of hardened flesh plates, with defined muscles all over. From each of his light gray arms, a tendril of darkened flesh expanded outwards. Mahito now no longer possessed eyes or ears, his head instead being covered by a strange plating that resembled crumpled paper, seemingly stitched to his head as the only remaining instance of stitches on his body. Most remarkably, Mahito now possessed a long gray tail.

“Wish me a happy birthday, Yuji.”

This transformation is different from his previous alterations, Yuji thought to himself, staring intently at his opponent’s new form. It looked almost a little scary, if not for Yuji already being used to seeing grotesque creatures. But what exactly is the difference?

“You know, Yuji, that black flash from earlier really made the true shape of my own soul clearer than ever before to me”, Mahito expressed, his voice sounding almost metallic now.

Yuji frowned, “Didn’t take you to be the type for a journey of self-discovery, Mahito”, earning himself a loud and metallic bout of laughter from his opponent.

“I’m surprised myself," Mahito calmed down again. “But the last step is still missing. Only once I’ve killed you will I finally be truly born in this world”, Mahito’s voice had lowered, sounding more like a whisper toward the end of his last sentence. Finally, his mouth contorted back into a grin.

Yuji lifted his foot off the ground. Mahito mirrored the movement. They took a step toward one-another. And another one. And then again. Yuji slowly picked up more speed, Mahito once again imitating him until finally, the two met each other's paths.

A leg was thrown toward the curse, who elected to deflect it using the tendrils on his arms, wrapping the clean black flesh around his opponent’s limb.

Yuji retaliated by forcefully ripping out the tendril and landing back on his legs, just to propel himself forward again, deflecting Mahito’s arm, with the sorcerer’s left fist landing in Mahito’s side and doing… absolutely nothing. A loud metallic sound of impact echoed throughout the battlefield, but Mahito didn’t budge.

He’s even more durable than the blood manipulator from earlier, Yuji realized, just to see a black tendril slicing at him once more. He jumped back to avoid the attack, but a moment too late. His shoulder had been hit. So that’s what he meant when he was talking about his soul’s true shape. He’s gotten stronger.

Mahito dashed toward Yuji again, the sorcerer dodging a flurry of attacks and attempting to retaliate. A pair of black tendrils was faster though, slashing open both of Yuji’s arms under the maniacal laughter of humanity’s curse.

Quickly recomposing himself, Yuji swung his damaged fists toward Mahito, who made no attempt to dodge or guard against the incoming storm of strikes. One impact after another filled the air, shockwaves reverberating all throughout Yuji’s body in recoil.

He couldn’t even scratch Mahito.

This monster is completely different from before his transformation!

Yuji was flung back by a tail swipe. Before he could even stand up again, Mahito’s hand already grabbed his face once more, dragging him through the rocky area and kicking up dust. The Jujutsu sorcerer closed his irritated eyes for just a moment, enough for Mahito to kick him into the air and follow him, landing a strike right into Yuji’s abdomen before grabbing his throat and shoving him into the ground with the speed of a fighter jet.

The ground collapsed under the force of the cursed spirit’s attack, letting both Yuji and his adversary plummet into a destroyed sewer below, now with an open roof.

If I want to defeat this guy, I’ll have to hit him with a black flash at full power, Yuji thought, slowly picking himself up again. His body had been torn up thoroughly by the beating he’d just endured, but Yuji’s limbs and organs still seemed intact for the most part. Yuji’s eyes shot wide open as his left leg gave out for but a second.

Without even giving the sorcerer time to breathe, Mahito instantly capitalized on the opening, dashing towards Itadori again. His left arm stretched out to deliver yet another salvo of attacks-

Blood sprayed out of Mahito’s mouth. His left elbow crumbled. The brat’s black flash after my domain expansion did more damage than I expected!, Mahito thought to himself. For a moment, he stumbled, disrupting his dash.

The sound of impacts could be heard from the direction of Mahito’s enemy. Yuji was punching his own knee. After being visibly satisfied with the result, he finally looked back at Mahito. Yuji’s gaze was focused intently on his opponent once more, who cackled, “Huh, seems like the both of us are still perfectly fine”.

Yuji didn’t give the curse the grace of responding. Mahito’s grin only widened even more, as he kicked the ground. A large wave of water exploded outwards from Mahito’s position, enveloping both fighters completely as Yuji reeled back his right fist and started intently focusing on his cursed energy.

The water was pushed back by the force of the negative emotions to reveal the curse of humanity as he once more dashed toward Yuji, attempting to slash him with his tendril blade. Yuji swiftly dodged out of the way, focusing energy into his fist once more to strike Mahito. The curse jumped back in shock.

Nobody can use black flash at will, Mahito pondered as he jumped around the area, but something makes me think that this guy now can.

Finally, Mahito once more decided to meet Yuji head-on. If that’s how it is…, Mahito stripped away the hardened skin on the left side of his body, …I’ll lure him in and then finish him after he’s wasted his chance!

Yuji’s fist hit Mahito’s side – It worked – and knocked the curse’s body back a little. The black blade on his right elbow shifted, preparing another punch.

Divergent Fist

But the punch never came, as Mahito’s left side was hit with a second impact.

Yuji once more accumulated energy in his fist. Aiming at the vulnerable side of Mahito’s face, the blue energy flared up violently. In utter shock, Mahito once more put up his arm, preparing to guard against the strike.

 

“Even you should realize this, cursed spirit”

 

Mahito heard the voice of Aoi Todo behind him, “Arms are merely a decoration. The act of applause is an acclamation of the soul!”

A bloody squelch echoed through the sewer when the gorilla clapped his hand against the stump on his other arm.

Anticipation of a new attack drove Mahito’s body around, That gorilla’s technique is the worst thing to happen right now

But a swap never came.

“Regrettably, my mighty Boogie Woogie… is already dead.”

That bastard!

Mahito turned around to face Yuji, but it was too late. Yuji’s fist hit his side, as Yuji exclaimed, “Black Flash!”

.

.

.

There was no black flash. Yuji’s eyes widened in shock. Mahito’s fear still clearly danced across his face, but slowly, a new emotion was creeping up on him. Glee. Yuji’s fist was still planted into Mahito’s side, but there was no more force behind it. He simply stood, staring at his motionless hand in terror.

Mahito’s face contorted again. Slowly, but with certainty, a grin formed.

“What was that again, Itadori?”, Mahito chuckled for a moment, before falling into an uncontrollable bout of mad laughter, “You really had me for a second there! I thought I was about to die, y’know?”, Mahito closely gazed upon Yuji’s eyes, gleefully watching the utter terror that was marking his facial features at the moment.

Yuji slowly retracted his trembling fist. Mahito’s words didn’t even seem to register in his mind at the moment. All that Yuji heard, was a deep voice from inside his head.

“Pathetic, brat. Losing to such small fry.”

Mahito was still cackling madly in front of him, “LOOKS LIKE THE BLACK SPARKS REALLY DON’T CHOOSE WHO TO BLESS, HUH?! I don’t even know why I was so scared! Yuji Itadori! I can finally kill you, isn’t that exciting?!”

Yuji’s gaze slowly moved back to meet Mahito’s own again. Yuji slowly bent his knees. He needed to get away. Right now.

The exhausted sorcerer jumped backwards, trembling still, but Mahito was faster. A palm strike hit Yuji’s head once again, knocking him straight into a stone wall. Yuji tried to pry himself free, but Mahito was already on him again.

“LET’S SEE HOW MUCH BETTER I AM THAN YOU, ITADORI!”

Black Flash

Mahito delivered a devastating sharp strike to Yuji’s abdomen, the boy spitting a mouthful of bright red blood. Mahito’s grin contorted almost beyond the bounds of his face, as a slight giggle left his throat.

Yuji’s vision went dark for a moment. He felt the rock behind his back break and shatter under the force of Mahito’s black flash. A shower of debris rained over the two combatants, but Yuji couldn’t even register it anymore. If I die here…, Yuji thought, I’ll fail everyone!

Memories flashed his mind, memories of his grandpa, of Aoi, Satoru, Nanami and Nobara. He’d fail all of them.

Yuji’s vision returned to him. He found himself being picked up by the collar and thrown to the ground by Mahito once more.

I’ll fail… everyone…

Mahito’s steps echoed through the area as he stepped toward Yuji. Slowly. Almost like he was trying to rub it in Yuji’s face. But the sorcerer didn’t even think of that, he was barely conscious after all. Memories kept flashing through his mind, memories of good times and not-so-good times, memories of his family and friends, memories of his old school, memories of his new school. Dreams that he once had and promises that he made.

The steps stopped.

That park he always played in as a kid. That bug cage he’d always used to catch grasshoppers with. That farm that Wasuke sometimes brought him to. Those silly competitions his teachers always used to challenge him to. That occult club he was in for the sake of his friends. The shitty movies he loved watching.

Mahito stretched out his palm and touched Yuji’s chest, who was still laying on the ground.

“No retaliation, really? You’re no fun! Can’t you dance for me once last time at the end, Itadori?”, Mahito said, finally more calm.

Yuji didn’t answer. A small smile formed on his face. Mahito’s voice felt like no more than the whispers of the wind. There was nothing else that Yuji could do anymore.

Everyone, I’ll leave the rest to you guys.

Mahito’s palm touched Yuji’s chest, “What a shame. I’d hoped to hear at least some last words. Though, maybe I’ll hear your screams from the afterlife once you realize what I’ll do”

Idle Transfiguration

Yuji’s eyes suddenly shot open once more, as Mahito’s technique activated.

For one brief moment, Yuji Itadori saw the stars in the sky one last time, before his eyes slowly closed again, his sight going dark and darker until he could see no more. Slowly feeling himself drift away, Yuji took a last breath before the cold feeling of death swallowed him whole.

Then, Yuji Itadori died.

Notes:

This is my first published work ever, and english isn't my first language, so please don't go too harsh on me. Costructive criticism is well appreciated though.

Adding onto that, Paired Falling Stars is supposed to be a whole story at some point, but I'm not yet certain if I'll be able to bring the necessary consistency to the table. Who knows, I might drop this project in a week or two. Don't expect too much for now. There will also not be a consistent upload schedule, since I'm doing this for fun and in my freetime.

Now for some actual chapter notes

One might think that I hate Yuji more than big man Gege himself hates him, you know, since I killed him off in chapter 1 and all.

All the memories that Yuji had are rooted in the actual manga btw. The bug cage he used to catch grasshoppers with, the farm his grandpa used to take him to etc. are all canon.

Mahito will be up to no good in this story. Look forward to his shenanigans. I must also say that it is mentally exhausting to write him.

What happened to Todo in the last part of the chapter? Who knows, I didn't think I'd get this far. Maybe we'll find out next chapter (yes, we, as in YOU and ME because neither of us know at the moment).

Thank you for reading if you got this far, god bless you!