A person in Japan, a sword that soars to immortality.

Edo Castle, Fujimi-yaguru.

Under the bright moon, a beautiful figure stood alone on the rooftop, gazing silently in the direction of Mount Fuji for a long time.

The gentle evening breeze lifted Muzan Kibutsuji's long hair, then scattered it into the air, letting it fall freely.

"The world changes... I hate change."

"This scenery... is truly nauseating."

Turning around, Muzan looked down at the entire Edo Castle. The landscape of that small village from a hundred years ago was gradually merging with the lights of thousands of homes before him.

She stood quietly for a while, and suddenly, countless slender tentacles emerged from her back, blotting out the sky and obscuring the stars.

If you look down from the sky, it's as if Edo Castle, which was originally bald, has suddenly been given a thick wig.

At that moment, both the samurai in the main keep and those patrolling the second naru looked up immediately as the moonlight suddenly disappeared.

Then, an unbelievable scene instantly came into everyone's view.

"Demon! Monster! Ugh!!"

Thousands upon thousands of tentacles, like a rain of arrows, swiftly pierced into each person's body.

These people immediately changed their expressions, froze in place, their pupils began to dilate, and their eyes became empty and lifeless.

"We can't find the blue spider lily, nor have we evolved a demon that can overcome sunlight."

"I must not attract the attention of the shogunate, otherwise it will become more troublesome once they realize my intentions."

I took a deep breath, feeling suffocated, and then a sense of powerlessness crept into my heart.

From the Heian period to now, nearly seven or eight hundred years have passed, yet the two things I care about most have made no progress at all.

Furthermore, even the Demon Slayer Corps, which were always at odds with them, failed to find the hideout of these people.

Now, the Twelve Demon Moons, on whom he had placed so much hope, have been defeated one after another by a human. This makes Muzan doubt himself, wondering if he has done something wrong.

She didn't really care what strange abilities her familiars evolved or how strong they became.

If Muzan had watched Naruto, he would definitely resonate with a line spoken by Madara Uchiha:

You... saw me at my peak?

If Blood Demon Art is also classified as magic, then Muzan can definitely be called the origin of all rivers and the source of all magic.

The only thing that can pique her interest right now is this samurai among humans named Yamada Asaemon Taichi.

"I never expected that the human warrior named Taiichi would be so powerful."

"But this energy... is not the breath of the sun, it is just full of some of the sun's essence."

A tentacle inserted into Tokugawa Ienari's body while he slept was reading the memories in his blood.

In doing so, Muzan also witnessed Taichi's various actions that day.

"I'm growing fast, but... even if I master the Breath of the Sun, so what? After all, the only one who can threaten me is him."

Involuntarily, Muzan placed his slender hand on his neck, and the image of Yoriichi Tsugikuni gradually appeared in his mind, along with the image of that day when he slashed across his neck.

In fact, Muzan doesn't really care much about the Breath of the Sun right now. Even if someone does master it, he'll most likely just send his familiars to kill them.

Even if Taichi mastered the Breath of the Sun, even if he defeated Kokushibo, so what?

At worst, we can just gather all the Upper Moon demons and attack together, and that will solve the problem.

In the original work, the task of eliminating the legacy of the Sun Breathing technique was undertaken by Kokushibo.

Only after Nezuko overcame the sunlight did Muzan choose to take action himself.

The person who could instill fear in Muzan was Yoriichi Tsugikuni.

For others, a clear view of the world means observing muscle textures and predicting movements.

For Yoriichi Tsugikuni, it was simply one of his abilities to see through the true nature of the world.

To dispel his mother's misunderstanding that he was deaf, he chose to speak.

In order to prevent his brother from losing his status as heir, he chose to run away from home.

In order to kill the demons, he created the Breath of the Sun, the Crimson Blade, and the Transparent World.

It was precisely because of his ability to see through everything that Yoriichi Tsugikuni was able to complete his sword form the instant he saw Muzan.

"How could there be a second person like this... Hmm? Elixir of immortality? Paradise Island? Four investigation teams were sent out, and all that came back were humans who had turned into flowers?"

"Recently, another group was dispatched, including elite constables specializing in apprehending criminals, as well as ninjas..."

After reading the memories from Tokugawa Ienari's mind, Muzan's eyes gradually widened, and his usually indifferent expression finally showed a slight change.

An island that can turn people into flowers...

An island covered with all sorts of magical flowers... the blue spider lily?

Immortality?

Muzan's nostrils flared involuntarily, and his breathing became heavy.

The last time I learned about this was when he turned the jade pot into a ghost, and I saw the scene from the fragments of his deepest memories.

However, after investigation, Muzan concluded that it was just an unforgettable dream that Gyokko had when he was very young.

When Yu Hu was alive, his original name was Yi Yu Yi. He grew up in a fishing village with parents who took care of him. He loved playing with fish and was very interested in them.

When he saw his parents drowned and their bloated bodies, he felt no sadness, but rather a sense of art.

After being turned into a demon by Muzan, Muzan discovered something different in his memories.

Giant carp, humanoid monsters that can wield the power of lightning, humans dominated by insects, and a dreamlike dragon coiled atop a giant cherry blossom tree.

"I searched all over the cherry blossom area, but I couldn't find the place in Yuhu's dream."

"But this magical island seems to really exist."

"An island covered in all kinds of flowers, an elixir of immortality... could it also have blue spider lilies there?"

Muzan's eyes gradually narrowed, and a slight smile slowly appeared at the corner of his mouth.

......

In a valley within the territory of the Himeji Domain.

Rows of thatched huts stood side by side, and in the very center, in the largest thatched hut, four ninjas wearing straw hats and cloaks with the Chinese characters for wind, forest, mountain, and fire printed on the back were kneeling on one knee.

Opposite them was a woman with a red diamond mark on her forehead, painted eyebrows, fox-like eyeliner, and a bewitching face. She was lying on her side, barefoot, watching them.

Meanwhile, a pure white fox lay down in front of the woman, closing its eyes for a nap.

"We've received intelligence that among the latest forces supporting Himeji Castle, there's a samurai named Yamada Asaemon Taichi." The woman continued, stroking the fox in her arms without looking up, "..."

"I want him unable to enter the main gate of Himeji Castle. Which of you... can do that?"

Of the four, the ninja with the character "mountain" printed on his back was the first to raise his head, his eyes flashing with cold killing intent, and he said calmly:

"Lord Mochizuki, I am willing to go. After all, Yamada Asaemon Taichi killed my disciple in Edo."

Chiyo Mochizuki, the leader of the Nezu ninja, nodded with satisfaction, and finally, with her lips slightly parted, she whispered:

"Go, Mountain Shadow."

"Kill Taiyi, and you will be the greatest in the world."