Muzan Kibutsuji

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Thud! Thud! Thud!

Kitaro summoned three identical shadow clones.

"Don't let anyone disturb me," he instructed.

The clones nodded and formed a protective perimeter.

Sitting cross-legged, Kitaro closed his eyes, steadied his mind, and swiftly formed hand seals.

When he opened his eyes again, he found himself in a dark, eerie space.

The ground resembled water, and before him stood a cage.

The moment he appeared:

Clang! Clang!

The sound of chains echoed, and soon, a figure almost identical to him emerged from the shadows of the cage.

The only difference was its feral, beast-like eyes.

"You! Let me out, you thief!" the figure roared, its face twisted with rage as it slammed against the bars.

Kitaro regarded it calmly. "Long time no see. Have you forgotten who you are? Muzan Kibutsuji."

Muzan Kibutsuji, the ultimate antagonist of Demon Slayer, the progenitor of all demons, and a being with near-immortality.

No matter the injury, Muzan could regenerate almost instantly. He was practically unkillable—except by sunlight.

Capturing and sealing Muzan within himself had been Kitaro's greatest achievement in the Demon Slayer world.

---

Using his Mangekyō Sharingan, Kitaro had crossed into the Demon Slayer world, where he mastered every breathing technique, including the original and strongest—Sun Breathing.

These skills significantly strengthened him, laying a solid foundation for his conquests in the ninja world.

But what truly held the most value in the Demon Slayer world wasn't the breathing techniques—it was Muzan Kibutsuji.

Muzan's immortality and regenerative abilities were priceless.

After defeating Muzan, Kitaro used sealing techniques to trap him within his own body, much like Naruto carried the Nine-Tails.

However, Muzan wasn't one to submit willingly. Over time, he attempted to infiltrate Kitaro's consciousness, seeking to take control.

But this was all part of Kitaro's plan. By deliberately loosening the seal, he absorbed Muzan's abilities, gaining traits like accelerated regeneration and limb regeneration—initially at the level of a basic demon, but eventually surpassing even the Upper Moons.

Now, Muzan's persistent infiltration had left his own consciousness blurred, and he was losing his sense of self.

Kitaro's mind had grown incredibly resilient from years of battling Muzan Kibutsuji's influence. This was the primary reason why, despite Muzan pouring so much of his power into the attempt, he could never fully take over Kitaro's body.

It was similar to Orochimaru's attempt to possess Sasuke, only for Sasuke to turn the tables and absorb his abilities instead.

Even so, Muzan's lingering presence was a potential threat Kitaro disliked having within himself. He had long been determined to eradicate Muzan completely, seizing all of his power for himself.

Initially, Kitaro planned to wait until Itachi awakened his Mangekyō Sharingan. Using the Tsukuyomi, he intended to kill Muzan gradually over time. However, while Itachi had now achieved this milestone, his current mental strength would take an unfathomable number of years to fully destroy Muzan.

Kitaro had even considered keeping Muzan sealed forever, ensuring he was no longer a danger.

But everything changed today when he mastered Conqueror's Haki—a form of spiritual power focused on mental dominance. After releasing his Haki on the Sabaody Archipelago, Kitaro swept away Muzan's infiltrating will within his own body in one decisive strike.

In that moment, his mind became clear, unclouded. Yet it was only after clearing his consciousness that Kitaro realized how deeply Muzan's subtle influence had affected him. Over the years, Muzan's insidious presence had gradually altered Kitaro's temperament, making him colder and more bloodthirsty—a fact even Kitaro himself had failed to notice.

Kitaro had thought of dominating the worlds because of that, now he made his direction to build an Alliance for all worlds.

---

Upon freeing his body of Muzan's taint, Kitaro reflected soberly: "In great dreams, who wakes first? Throughout this life, I alone know myself."

Now fully aware, Kitaro knew it was time to deal with Muzan once and for all. This lingering threat could not be ignored any longer.

In the prison where Muzan Kibutsuji had been sealed for six years, the demon began to mutter, his crimson eyes sharpening with clarity.

"Muzan Kibutsuji... Muzan Kibutsuji…"

Then his voice grew resolute:

"Yes… that's right! I am the progenitor of all demons—Muzan Kibutsuji!"

As Muzan spoke, his appearance began to shift, transforming back into his original form as seen in Demon Slayer: jet-black, wavy hair, a tall and slender build, paper-white skin, and deep crimson eyes.

Muzan raised his head, his icy gaze filled with killing intent as he stared at Kitaro and uttered his name.

"Uchiha… Kitaro…"

Through the memories embedded in Kitaro's cells, Muzan had learned of his identity. An otherworldly traveler, capable of astonishing feats—it explained why Kitaro was so powerful. Yet, no matter who Kitaro truly was, it didn't diminish Muzan's hatred.

For the first time in his existence, Muzan had been imprisoned—and for six agonizing years. This humiliation burned into his soul.

"Recognized me at last?" Kitaro asked with a smirk.

Muzan glared at him warily. "What do you want? Why are you here?"

Their last battle was etched into Muzan's memory. Despite Kitaro being only twelve years old, he had single-handedly stormed Infinity Castle, massacred all of Muzan's subordinates, and sealed him in this prison. The boy had grown into a man now, and Muzan instinctively knew he was far more dangerous.

"To set you free, of course!" Kitaro said, grinning.

"Free me? You, of all people, would never do something so kind. What are you plotting?" Muzan's voice was laced with suspicion. He viewed Kitaro as the most cunning and deceitful individual he'd ever encountered in over a thousand years.

Feigning indignation, Kitaro replied, "You wound me, Lord Muzan! I simply want to let you go. After all, if I let you keep festering inside me, I might lose myself entirely. To avoid becoming another version of you, my only choice is to release you! Surely, you'll be magnanimous enough to overlook my past actions?"

"Ridiculous!" Muzan sneered, though he didn't doubt Kitaro's reasoning. To have resisted his infiltration for so long was a miracle in itself.

"Well then," Kitaro said, stepping forward, "time to undo the seal." He reached out and tore away the talisman that bound Muzan.

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