Ancient Kyoto

Arriving at the training grounds, I saw a group of young swordsmen working hard to practice their breathing techniques and swordsmanship; in the lightning-fast moments of their blade swings, elemental powers of Earth, Wind, Water, and Fire were beginning to manifest.

Clearly, these swordsmen had already mastered the rudimentary forms of branch breathing styles.

Tsugikuni Yoriichi was right there among them, guiding some of the swordsmen with lesser aptitude.

In every world, there is never a shortage of geniuses, much like the Hashira established later in the Demon Slayer Corps, each one a breathing technique prodigy unlike any ordinary person.

These Demon Slayer Corps swordsmen were either raised by the Ubuyashiki family from a young age or were elites who had survived life-or-death struggles against demons.

Some geniuses only needed a slight nudge from Tsugikuni Yoriichi to learn, or even to develop their own breathing styles.

However, the other portion with weaker aptitude required Tsugikuni Yoriichi to teach them with meticulous care.

Fortunately, Tsugikuni Yoriichi possessed the necessary patience.

"Lord Sarutobi!"

"My lord!"

Seeing Sarutobi Hiruzen arrive, the many practicing warriors quickly set down their blades and addressed Sarutobi Hiruzen respectfully.

Although Sarutobi Hiruzen did not teach them ninjutsu, he was an honored guest respected by the Ubuyashiki patriarch.

And the strength Sarutobi Hiruzen had displayed was something they, who had only just begun learning swordsmanship, could hardly reach.

Sarutobi merely nodded in response upon seeing this, then walked straight up to Tsugikuni Yoriichi.

He did not speak to Tsugikuni Yoriichi immediately, waiting instead until Tsugikuni Yoriichi had finished instructing the swordsmen before opening his mouth.

"Yoriichi."

"How is the progress lately?"

Sarutobi Hiruzen asked.

"Basically, all the swordsmen of the Demon Slayer Corps have learned the breathing techniques."

Tsugikuni Yoriichi smiled, looking quite gratified.

"What remains is just a matter of proficiency..."

Sarutobi Hiruzen, however, looked helpless; who cared about the progress of those swordsmen?

"I am talking about the progress regarding the breathing technique adapted for me."

"Besides, no matter how proficient they become, they won't be able to reach a realm like yours, will they?"

Tsugikuni Yoriichi smiled sheepishly.

"A fellow like me is nothing special..."

"In the future, there will surely be swordsmen capable of surpassing me."

"As for the breathing technique you requested, Mr. Sarutobi,"

"I already have a direction."

Tsugikuni Yoriichi said.

"It is just that I still need some of your suggestions..."

"After all, the breathing technique you require is not in the same system as the ones I usually use..."

Ordinary breathing techniques were all about squeezing and training the body's capabilities, whereas Sarutobi Hiruzen's request went in the opposite direction.

Wanting to nourish and repair one's own physical abilities was a test even for Tsugikuni Yoriichi.

Fortunately, Tsugikuni Yoriichi's talent was enough to put Sarutobi Hiruzen's mind at ease.

"You already have a lead!"

Sarutobi Hiruzen was somewhat pleasantly surprised.

"Yes..."

"If the goal is merely to extend one's lifespan..."

Tsugikuni Yoriichi became very serious and earnest when discussing his craft.

"It is still quite easy to achieve."

"But I believe your thoughts, Mr. Sarutobi, go beyond that..."

"Is there anything you have a preference for?"

"Or rather, are there any fluctuations you wish to emulate and learn?"

Upon hearing this, Sarutobi Hiruzen also fell into deep thought.

He understood that what Tsugikuni Yoriichi was asking about referred to the elemental affinity of the breathing technique.

"I do not have any particular preference myself..."

Sarutobi Hiruzen shook his head.

"If I had to say, whether it be Earth, Wind, Water, Fire, or Lightning..."

"I am proficient in all of them."

"What?"

This time, it was Tsugikuni Yoriichi's turn to wear a strange expression.

Possessing the attributes of Earth, Wind, Water, Fire, and Lightning for breathing styles simultaneously—that was something only a deity could achieve.

One would likely need to grow five lungs to manage it; even Tsugikuni Yoriichi could only utilize one breathing style attribute at a time.

"Just a joke..."

Sarutobi Hiruzen chuckled. Making the composed Tsugikuni Yoriichi change his expression was quite amusing.

Although he wasn't lying; he truly was proficient in all five attributes.

It was just that such elemental attributes likely couldn't compare to an attribute that could extend one's lifespan.

"If I had to name a preferred attribute..."

A glint flashed in Sarutobi Hiruzen's eyes, as if he had thought of something.

"That would be..."

Kyoto, Even though the Land of Days was a small nation with a sparse population, as the capital city of the country, it was still quite prosperous.

At the very least, compared to the desolate scenes Sarutobi Hiruzen had seen along his journey, the Kyoto before him felt like a true ancient city.

Buildings stood row upon row, and people came and went in a constant stream.

Even at night, countless oil lamps were lit, illuminating the streets as if it were broad daylight.

While the headquarters of the Demon Slayer Corps was far from the city center, it still belonged to the Kyoto region, and it hadn't taken long to reach—only a little over half a day by carriage.

Sarutobi Hiruzen had come down the mountain in search of experimental subjects. He felt that Kyoto, with its dense population, would not lack people, nor would it lack demons. Such a large population should be able to sustain quite high-level demons.

At the same time, he took the opportunity to tour the capital and experience the local customs and culture of the ancient Land of Days.

Sarutobi Hiruzen was dressed in a white robe, accompanied by Masahiro, who carried a sword. His slightly graying beard, paired with a dignified face, exuded the authority of a high-ranking official.

Passersby bowed and stepped aside upon seeing them, all assuming Sarutobi Hiruzen was some great personage, fully demonstrating the spirit of the "bowing craftsman."

"My lord."

"Kyoto at night is quite lively..."

"If you do not like it, you may rest first."

Masahiro bowed slightly. Seeing Sarutobi Hiruzen's indifferent expression, he assumed Sarutobi Hiruzen did not care for the environment.

After all, traveling by carriage in this era was still quite bumpy.

"No need..."

"I will just walk around."

Sarutobi Hiruzen declined Masahiro's suggestion.

The bumps of the carriage had almost no effect on a ninja's physical constitution.

It was just that, having lived two lives, Sarutobi Hiruzen felt no novelty toward these bustling scenes. At most, he would take a few extra glances, but he would not reveal his emotions on the surface.

The streets of Kyoto at night still had many stalls selling exotic items or snacks.

However, after taking a few looks or smelling the scents, Sarutobi Hiruzen lost interest.

No matter how strange things in this era might be, it was still just an ordinary ancient world.

Even the extraordinary Demon Slayer Corps and the demons remained hidden behind the scenes, not exposed to the world at large.

Clearly, the history of ordinary people was the main theme of this world.

"As expected, even if I am interested in my heart..."

"Having integrated the memories of the Third Hokage, I already feel a deep sense of detachment from this kind of mundane, ordinary life."

"In my past life, I experienced prosperity far greater than what is before me."

"Now, I only wish to glimpse the infinite extraordinary."

Sarutobi Hiruzen shook his head, feeling that he could not integrate into this era.

"However..."

"Since the main tone of this world is ordinary history..."

"If I could transform this world into a world of extraordinary power..."

"The amount of Space-Time Source Energy I could obtain would likely be massive."

Sarutobi Hiruzen thought to himself.

"It's just that, for me right now, it's likely difficult to achieve..."

"Teaching a few people to learn Chakra is easy."

"But to popularize Chakra and influence the historical progress of technology..."

"I would probably have to bring the Ten-Tails Divine Tree over here."