The decision crystallized during a quiet evening on Uzushio Island, six months after Kenjaku's first encounter with the King of Curses.
He had been reviewing intelligence reports, tracking Sukuna's movements through the network of informants he'd cultivated across the mainland. The sealed King had not been idle during their separation. Despite losing his Domain Expansion, despite being stripped of Cleave and Dismantle, despite the existential decay slowly consuming his physical form—Sukuna had been hunting.
Hunting for information about the being who had humiliated him.
Hunting for weaknesses to exploit.
Hunting for Kenjaku.
The reports painted a picture of methodical rage. Sukuna had tortured dozens of sorcerers, seeking anyone with knowledge of soul-manipulation techniques. He had destroyed three minor clans whose territories bordered the Shimoda lands, apparently operating on the theory that proximity implied connection. He had even attempted to contact the remnants of ancient jujutsu families, offering power in exchange for information.
And he was getting closer.
Two weeks ago, Sukuna had captured a merchant who had traded with Uzushio Island. The merchant had been found three days later, still technically alive but missing most of his skin and all of his sanity. Before his mind had shattered completely, he had apparently revealed the existence of a "stitched sorcerer" visiting the Uzumaki.
Sukuna now knew where Kenjaku was.
The King would come. That was inevitable. His pride, his rage, his absolute refusal to accept limitation—all of it demanded confrontation. Every day that passed brought him closer to Uzushio, closer to the battle that would determine which of them survived.
Kenjaku could wait. Could prepare defenses, set traps, arrange the battlefield to his advantage. The Uzumaki's barrier techniques combined with his own abilities could create a defensive position that even Sukuna's diminished power would struggle to breach.
But that wasn't what Kenjaku wanted.
He didn't want to defend. Didn't want to react. Didn't want to let Sukuna dictate the terms of their final encounter.
He wanted to hunt.
He wanted to find the King of Curses on his own terms, in a location of his own choosing, and demonstrate once and for all that Ryomen Sukuna was no longer the apex predator of this era.
He wanted to kill a god.
"I'm leaving tomorrow," Kenjaku announced to Hana that evening. "Alone. I may be gone for several weeks, or I may return within days. It depends on how quickly I can locate my target."
Hana's reaction was immediate and visceral—her face paled, her hands trembled, her eyes filled with the desperate fear of separation that had become her constant companion.
"Master, please—let me come with you. Whatever you're hunting, I can help. I can—"
"You would die." Kenjaku's voice was gentle but absolute. "The opponent I'm facing would kill you in the first second of combat, and your death would distract me at a critical moment. You serve me better by remaining here, maintaining our cover with the Uzumaki, and continuing to gather intelligence."
"But—"
"Hana." He caught her chin, forcing her to meet his eyes. "I am not asking for your opinion. I am informing you of my decision. You will obey."
The command wasn't enhanced with Cursed Speech, but it didn't need to be. Hana's conditioning was complete enough that his normal authority sufficed. She subsided, tears streaming down her face, her body language radiating misery that she made no attempt to hide.
"Promise me you'll come back," she whispered. "Promise me you won't leave me alone."
Kenjaku considered the request. Promises were dangerous things in a world where binding vows had literal power. But this wasn't a binding vow—it was simply words, carrying no more weight than he chose to give them.
"I promise," he said. "I will return to you."
The words meant nothing to him. But they meant everything to her, and her visible relief was useful for maintaining her psychological stability during his absence.
He departed at dawn, leaving Uzushio Island by the same route he had first arrived. The crossing to the mainland was smooth, the morning mist parting before his small boat like a curtain being drawn aside.
The hunt had begun.
Tracking Sukuna was simultaneously easy and difficult.
Easy because the King of Curses made no effort to hide his presence. His spiritual pressure was a beacon that could be sensed from miles away, a constant declaration of power that lesser beings learned to avoid. Sukuna didn't sneak or skulk or conceal himself. He walked openly, daring anyone to challenge him.
Difficult because that same overwhelming presence made direct approach suicidal for most sensors. Getting close enough to pinpoint Sukuna's exact location meant entering the range of his spiritual pressure, which meant announcing your presence to a being who killed on reflex.
Kenjaku was not most sensors.
His expanded cursed energy reserves and refined perception allowed him to track Sukuna from a safe distance, following the King's trail of destruction across the northern territories. The path was marked by corpses, by burned villages, by the absolute silence of regions where even insects feared to make sound.
Sukuna was heading south. Toward the coast. Toward Uzushio Island.
Kenjaku intercepted him on the third day, in a valley that had once held a farming village but now held only ash and memory.
The King of Curses stood in the center of the devastation, four arms crossed, both faces wearing expressions of bored contempt. Around him, the remains of his latest victims were arranged in patterns that might have been artistic or might have been purely sadistic.
"I knew you'd come," Sukuna said, without turning around. His voice carried across the ruined valley like thunder across an empty sky. "The moment I started moving toward your little island, I knew you'd try to stop me before I arrived. You're not the type to hide behind others' defenses."
Kenjaku descended from the ridge where he'd been observing, making no attempt at stealth. There was no point—Sukuna had sensed him long before he'd sensed Sukuna.
"You're dying," Kenjaku observed, noting the subtle signs of deterioration in the King's physical form. The seal he'd placed months ago was working exactly as designed, slowly eroding Sukuna's existence. "Another year, maybe two, and you'll fade entirely. Why not spend your remaining time enjoying yourself rather than pursuing revenge?"
Sukuna's smile was terrible. "Because revenge IS enjoyment. Because making you suffer will bring me more pleasure than a thousand years of idle entertainment. Because you DARED to touch what was mine—my power, my techniques, my destiny—and that offense demands payment in kind."
He turned finally, all four eyes fixing on Kenjaku with killing intent so concentrated it was almost visible.
"I'm going to break every seal you've placed on me. I'm going to reclaim everything you stole. And then I'm going to spend the next century teaching you the true meaning of pain."
Kenjaku's smile matched the King's in its wrongness.
"You're welcome to try."
The battle began without further preamble.
Sukuna moved first, his four arms becoming a blur of motion as he closed the distance between them. Without Cleave and Dismantle, he was forced to rely on pure physical combat—but "pure physical combat" from the King of Curses was still devastating beyond mortal comprehension.
His first punch would have shattered a mountain.
Kenjaku wasn't there to receive it.
He had activated his enhanced perception the moment Sukuna twitched, reading the attack's trajectory before it fully formed. His body twisted aside with milliseconds to spare, the wind displacement alone enough to tear his clothes and leave shallow cuts across his skin.
Counter.
Black Flash.
His fist connected with Sukuna's exposed side, the spatial distortion erupting with its distinctive black spark. The enhanced impact sent the King stumbling—not falling, Sukuna was too powerful for that—but visibly moved for the first time in their encounter.
"What—" Sukuna's eyes widened fractionally. "That technique. You can use it deliberately?"
"Every single time." Kenjaku pressed his advantage, launching a combination of strikes that each carried Black Flash's 2.5x enhancement. "I've had months to improve, Sukuna. Did you think I spent them idle?"
The flurry of attacks pushed the King back across the ruined village, each impact creating shockwaves that scattered ash and debris. Sukuna blocked, dodged, countered—his combat instincts undiminished despite his sealed techniques—but he was clearly struggling to adapt to Kenjaku's enhanced physical output.
This wasn't the same opponent he'd faced months ago.
This was something evolved.
Something dangerous.
Sukuna snarled and increased his own output, all four arms working in devastating coordination. His counterattack was a storm of violence, hundreds of strikes per second, each one carrying enough force to pulverize steel.
Kenjaku's enhanced perception mapped every attack, his modified reflexes responding with inhuman precision. He wove through the assault like water through rocks, never quite where Sukuna's fists expected him to be, always positioned for optimal counter-strikes.
Black Flash. Black Flash. Black Flash.
Each connection added to the damage accumulating on Sukuna's body. The King healed rapidly—his vitality was immense even in his diminished state—but he wasn't healing faster than Kenjaku was hurting him.
For the first time in his existence, Ryomen Sukuna was losing a purely physical confrontation.
"ENOUGH!"
The roar carried spiritual weight that transcended sound, Sukuna's overwhelming cursed energy exploding outward in a wave that leveled everything within fifty meters. Trees became splinters. Rocks became dust. The very ground cratered beneath the King's fury.
Kenjaku was thrown backward, his defensive techniques barely absorbing the impact. He landed in a crouch, immediately ready for the follow-up attack—
Which didn't come.
Instead, Sukuna stood in the epicenter of his destruction, breathing heavily, his four eyes burning with something that might have been respect buried beneath layers of rage.
"You've improved more than I anticipated," the King admitted. "Your physical capabilities now approach my own. Your reaction speed may actually exceed mine. If this were merely a contest of martial skill, you might eventually prevail."
His smile returned, carrying promise of horrors to come.
"But I am not merely a martial artist. I am Ryomen Sukuna. And even without my sealed techniques, I have power that your little modifications cannot match."
He raised all four arms, cursed energy gathering in quantities that made the air itself scream. This wasn't a technique—it was pure spiritual pressure, condensed and weaponized into something that defied categorization.
"LET ME SHOW YOU WHAT TRUE POWER LOOKS LIKE."
The attack was less an ability than a natural disaster.
Sukuna's accumulated cursed energy erupted in all directions simultaneously, a spherical expansion of absolute destruction that annihilated everything it touched. Not through heat or force or any physical mechanism—but through spiritual weight so massive that existence itself couldn't bear it.
Kenjaku had approximately one tenth of a second to respond.
In that fraction of a moment, his mind raced through options and discarded them just as quickly. Dodging was impossible—the attack was omnidirectional. Blocking was suicide—no defense he possessed could withstand that level of power. Running was pointless—the expansion would catch him before he moved ten meters.
Only one option remained.
"Domain Expansion."
The words left his mouth even as Sukuna's attack reached him. Reality shattered, not from the King's power but from Kenjaku's, his inner world manifesting with desperate speed.
The Library of Forbidden Wisdom bloomed into existence.
The infinite shelves appeared first, towering structures of knowledge that stretched beyond perception. Then the books, millions of volumes containing everything Kenjaku had ever learned or experienced. Finally, the machine at the center—the great apparatus of modification that represented his technique's absolute expression.
Sukuna's attack hit the domain's boundary and... stopped.
The spiritual pressure was immense, enough to strain the library's walls to their absolute limits. Kenjaku could feel his cursed energy draining rapidly, the cost of maintaining his domain against such overwhelming force pushing him toward exhaustion.
But the boundary held.
Inside the Library of Forbidden Wisdom, Kenjaku's will was law. Outside forces, no matter how powerful, could not simply force their way through.
"A Domain Expansion," Sukuna observed, his attack subsiding as he recognized the futility of raw power against a manifested inner world. "Interesting. I didn't know you possessed one."
"There's quite a lot you don't know about me."
Kenjaku's voice echoed through the infinite library, carrying from everywhere and nowhere simultaneously. He was the domain, and the domain was him. Within these walls, he was as close to omnipotent as any being could be.
"You've entered my world now, Sukuna. Here, my techniques are absolute. My will cannot be denied. My modifications require no contact and permit no resistance."
He raised his hand, and the machine at the center began to move.
"Here, I can do anything I want to you. Reshape your body. Rewrite your mind. Erase your existence entirely."
Sukuna's expression didn't change, but something flickered in his eyes—not fear, exactly, but recognition of genuine danger.
"Then do it," the King challenged. "If you're as powerful as you claim, transform me. Destroy me. Show me this absolute authority you boast of."
Kenjaku activated Idle Transfiguration through his domain's mechanism.
The technique reached for Sukuna's soul, attempting to reshape the King of Curses into something harmless. The machine whirred, the books rustled, the very fabric of the library bent toward the task of modification.
And Sukuna... resisted.
Not through technique or ability or any mechanism that Kenjaku could identify. Simply through the sheer weight of his existence, the absolute certainty of his self-identity. Sukuna's soul rejected modification because Sukuna rejected modification—his will was so powerful that even a domain's sure-hit effect couldn't simply override it.
The attempt failed.
Kenjaku's eyes widened in genuine surprise. "That's... impossible. Domain Expansion guarantees—"
"Guarantees nothing against a king." Sukuna's smile was triumphant. "Your domain is impressive, little monster. But I am Ryomen Sukuna. I have never been what others tried to make me. And I never will be."
He began walking forward, pushing against the domain's pressure through sheer force of presence.
"Your sure-hit fails against my soul. Your guaranteed modifications cannot touch my identity. All your clever techniques, all your stolen knowledge, all your months of preparation—none of it matters against absolute, unconditional pride."
Each step brought him closer to Kenjaku, closer to the machine, closer to the domain's heart.
"This is the difference between us. You've grown strong through accumulation—gathering techniques, modifying yourself, building power from pieces. But I was born complete. I am what I am, and what I am is beyond your comprehension."
Kenjaku's mind raced as Sukuna advanced. The King was right—pure Idle Transfiguration wasn't working against his overwhelming self-identity. The domain's sure-hit effect was being negated by something that transcended normal spiritual mechanics.
But Kenjaku hadn't survived for centuries by relying on single techniques.
"Cursed Speech."
He spoke the words with maximum power, infusing them with every drop of cursed energy he could spare while maintaining his domain.
"STOP."
The command hit Sukuna like a physical blow, his advance halting mid-step. For a moment—just a moment—the King was frozen, his body obeying the compulsion despite his will's resistance.
Then he pushed through.
"Clever," Sukuna acknowledged, resuming his advance. "But not clever enough. Your commands can delay me, not stop me."
"I don't need to stop you."
Kenjaku's smile returned, carrying confidence that Sukuna found suddenly concerning.
"I just needed to buy time."
The machine at the domain's center completed its real task.
Not modifying Sukuna—Kenjaku had realized immediately that direct transformation was failing. Instead, the machine had been working on something else entirely.
The domain itself.
The Library of Forbidden Wisdom shuddered, its walls contracting, its shelves compressing. The infinite space was becoming finite, the endless expanse collapsing into something concentrated and purposeful.
Sukuna felt the change immediately—felt the domain tightening around him like a closing fist.
"What are you doing?"
"Something I developed specifically for opponents I can't simply transform." Kenjaku's form began dissolving into the library's structure, his consciousness merging with his domain's fabric. "If I can't modify your soul directly, I'll simply contain it. Permanently."
The domain's final configuration revealed itself.
It was no longer a library. It was a cage.
Every book, every shelf, every aspect of the space had been reconfigured into layers of sealing, Uzumaki techniques integrated into the domain's very nature. The walls weren't walls anymore—they were binding arrays, spiritual chains, imprisonment made manifest.
And at the center, where the modification machine had been, there was now only a single point.
A singularity of sealing power, designed to contain one specific being.
"YOU PLANNED THIS." Sukuna's roar shook the compressed domain. "FROM THE BEGINNING, YOU PLANNED TO TRAP ME."
"Of course." Kenjaku's voice came from everywhere, from the walls themselves. "I knew direct confrontation was risky. I knew my modifications might fail against your overwhelming identity. So I developed a contingency. A prison built from a domain expansion, combining my technique with Uzumaki sealing traditions to create something you cannot break."
Sukuna lunged toward the walls, his fists impacting with force that should have shattered reality. The sealing arrays absorbed the impact, converting his power into fuel for their own binding.
"You'll never hold me forever!"
"I don't need forever. I only need until the other seals I placed on you complete their work." Kenjaku's presence concentrated briefly, forming a face in the domain's fabric—that distinctive smile, those stitched features, those eyes that never quite showed warmth. "Remember the seal that's eroding your existence? It's still active. Still working. Every day that passes, you become slightly less real."
He paused, letting the implication sink in.
"Within this prison, time passes differently. From your perspective, years might go by. Decades. But outside, only days will elapse. And when your existence finally fails—when the seal consumes the last of what you are—this domain will dissolve naturally. Releasing nothing but empty space."
Sukuna's face contorted with fury beyond expression. "I AM RYOMEN SUKUNA! I AM THE KING OF CURSES! I WILL NOT END LIKE THIS!"
"Every king falls eventually." Kenjaku began withdrawing from his domain, leaving Sukuna trapped within. "But take comfort, Sukuna. Your death contributes to something greater than yourself. When you're gone, I'll be free to pursue my plans without the threat of your interference. Your hatred, your rage, your endless pursuit—all of it will end, and I will continue."
The domain stabilized into its final prison configuration. Sukuna was visible inside, a figure of impotent rage trapped within walls that converted his fury into their own reinforcement.
"Any last words?" Kenjaku asked, almost conversationally.
Sukuna stopped struggling. His face—both faces—went still, and when he spoke, his voice carried something that Kenjaku had never heard from him before.
Cold, absolute certainty.
"You think you've won. You think this cage can hold me forever. But I've existed for centuries, little monster. I've been sealed before. I've been contained, imprisoned, bound by techniques that your predecessors thought were permanent."
His smile returned, and it was somehow more terrible than his rage had been.
"I always get out. And when I do—no matter how long it takes—I will find you. Not your body. Not your current host. YOU. Whatever vessel you're wearing, whatever identity you've adopted, whatever power you've accumulated. I will find the core of what you are, and I will destroy it so completely that not even memory of your existence will remain."
Kenjaku held Sukuna's gaze for a long moment.
"I look forward to it," he said finally. "Goodbye, Sukuna. Enjoy your eternity."
He released his hold on the domain's external interface, leaving the prison to sustain itself. The compressed space would persist as long as its internal sealing arrays remained powered—and since those arrays fed on Sukuna's own energy, they would persist exactly as long as the King himself survived.
A perfect trap.
A perfect victory.
A perfect end to the threat that had loomed over all his plans.
Kenjaku stood alone in the ruined valley, looking at the spot where his domain had manifested. There was nothing visible to mark Sukuna's prison—the cage existed in a dimensional space adjacent to reality, perceptible only to those who knew where to look.
The King of Curses was gone.
Not dead yet—that would take months, maybe years, as the existence-eroding seal did its slow work. But effectively removed from the world. Unable to interfere. Unable to threaten.
Unable to compromise anything Kenjaku was building.
The relief that washed through him was almost physical. He hadn't realized until this moment how much of his consciousness had been devoted to contingency planning around Sukuna, how much mental energy had been consumed by preparing for their inevitable rematch.
Now that energy was free.
Now he could focus entirely on the future.
On Madara and Hashirama and the founding of the hidden villages.
On the Otsutsuki and their planetary ambitions.
On Naruto and Sasuke and the eventual inheritors of the shinobi world.
On all the challenges that remained, all the threats that would emerge, all the opportunities that waited to be seized.
Kenjaku began walking south, toward the coast, toward Uzushio Island and the next phase of his plans.
Behind him, invisible and inescapable, a king screamed his rage into a prison that would be his tomb.
The greatest threat of the current era had fallen.
And the greatest villain of all time continued his ascent.
The battle was over.
The victory was complete.
But the story was only beginning.
Kenjaku reached Uzushio Island three days later, his body still recovering from the strain of the battle. Maintaining a domain expansion for that length of time, while simultaneously converting it into a prison configuration, had pushed his cursed energy reserves to dangerous lows.
But he was alive.
And Sukuna was not.
Well, not yet. But effectively so.
Hana met him at the harbor, her face shifting through a dozen emotions as she registered his return. Relief. Joy. Concern at his obvious exhaustion. Adoration that had only intensified during his absence.
"Master!" She ran to him, stopping just short of physical contact as she always did, waiting for permission that she both craved and feared. "You're back. You're safe. What happened? Did you find—"
"It's done." Kenjaku allowed her to take his arm, supporting him as they walked toward the village. "Sukuna is contained. He won't be threatening us again."
"Contained? You mean—"
"I mean exactly what I said. He's trapped in a prison of my own design, sustained by his own power, slowly being eroded by the seals I placed on him months ago. Within a year, perhaps less, he'll cease to exist entirely."
Hana's eyes went wide with awe. "You defeated the King of Curses. You actually defeated him."
"I did more than defeat him. I made him irrelevant." Kenjaku's smile carried exhausted satisfaction. "One less variable to account for. One less contingency to plan around. The future just became significantly more manageable."
They walked in silence for a while, Hana processing the magnitude of what he'd accomplished. The King of Curses—the most feared being in jujutsu history—had been eliminated by her master. The stories that would eventually be told about this day would reshape how sorcerers understood power.
But no one would ever know the truth.
Because Kenjaku didn't want credit. He wanted freedom.
Freedom to operate without Sukuna's shadow looming over him.
Freedom to pursue his plans without the constant threat of interruption.
Freedom to become whatever he chose, without a rival powerful enough to challenge him.
"What happens now?" Hana asked, as they approached the Uzumaki village.
Kenjaku looked toward the east, where the mainland stretched beyond the horizon. Somewhere out there, children were growing into legends. Madara and Hashirama were developing the powers that would reshape the shinobi world. The seeds of hidden villages were being planted in the minds of visionaries who didn't yet know what they would build.
"Now," he said, "we prepare for the future. The real work is about to begin."
Hana nodded, not understanding but not needing to. Her master had returned victorious. Her master would tell her what to do next. Her master would lead her through whatever challenges lay ahead.
That was enough.
That would always be enough.
Above them, the sun broke through the morning clouds, casting golden light across Uzushio Island. It was a beautiful day—the kind of day that poets wrote about, that lovers remembered, that heroes saw as omens of good fortune.
For Kenjaku, it was simply the first day of the rest of eternity.
A future he would shape according to his will.
A story he would write in blood and ambition.
A legend that would echo through generations.
The King of Curses had fallen.
The Accursed Sage of Calamity remained.
And the world would never be the same.