Line of Interval

A week later, after handling his father's funeral, Kujo Tachibana opened the final letter his father had left him...

Even now, ten years after arriving in this world and recovering his memories, Tachibana still had no idea what kind of place he had come to.

At first, Kujo Tachibana had thought he'd traveled back in time to nineteenth-century Japan.

But over the years, he'd gradually begun to sense that something was wrong.

The history, the geography, and other details all conflicted with the memories of his previous life.

Only today, after reading his father's final letter, did Tachibana finally understand!

What kind of world he had come to.

"Tachibana."

"I have nothing left to teach you about swordsmanship."

"I only hope you'll carry on what your father has passed down to you and keep climbing toward the pinnacle of swordsmanship!"

"What I'm about to tell you is very important. I hope you'll remember it well!"

"In this world, there are terrifying creatures called demons. They have sharp claws and fangs, and the strength of wild beasts. They come out at night and feed on human flesh and blood. Ordinary swords and weapons can't harm them at all."

"Only sunlight and a special weapon called a Nichirin Sword can sever a demon's neck and destroy it completely."

"These Nichirin Swords can only be forged by a special organization called the Demon Slayer Corps. The Corps and the demons have been at war for over a thousand years."

"Heh. Tachibana, do you think your father's joking?"

"I wish this were only a joke, too. And I hope you never encounter a demon."

Nichirin Swords, the Demon Slayer Corps... Familiar words drifted through Kujo Tachibana's mind.

Memories of his previous life rose to the surface.

"Demon Slayer?"

"Not bad."

Three months later, in the Kujo family courtyard.

Kujo Tachibana gripped a long, traditional Japanese sword in both hands, staring intently at the enormous boulder in front of him.

It was a sword his father had once carried.

The blade was eighty centimeters long, and the entire sword measured one hundred and ten. Its gleam in the sunlight was enough to make anyone's heart skip a beat. It was a true weapon.

Tachibana held his stance without swinging, slowly adjusting his breathing as he stared at the boulder.

He hadn't learned a Breathing Style yet, but he knew how to regulate his breathing so his body could exert force more effectively.

In Demon Slayer, before Tanjiro took the Demon Slayer Corps' selection exam, his teacher, Urokodaki Sakonji, had set him an incredibly difficult trial so he wouldn't throw his life away.

The trial was to cut through an enormous boulder with a sword. It took Tanjiro a year, and with the help of the spirits of Makomo and Sabito, he finally sensed the Line of Interval and cleaved the rock.

The boulder in front of Kujo Tachibana was a trial he had set for himself.

He wouldn't leave the Kujo estate to search for the Demon Slayer Corps until he could cut it in two. Traveling far from home would be dangerous otherwise.

He wasn't afraid of running into people.

What worried him was the chance of getting unlucky and encountering a powerful demon in the wild. That would be trouble.

Tachibana didn't want to be reincarnated again. Who knew if he'd get another chance to start over?

He thought he could handle ordinary demons.

His swordsmanship was no worse than that of the Hashira in Demon Slayer, and he also had Clear Sword Heart to bolster him.

Kujo Tachibana thought, With the same physical abilities, the Hashira in the world of Demon Slayer probably couldn't beat me, right?

But without a Breathing Style, his physical abilities and explosive power still fell far short of theirs.

As for the Line of Interval, Kujo Tachibana had sensed it six months earlier, when he reached the Sword Heart Clarity realm. But he still lacked the explosive power to cut through the boulder in front of him.

As Tachibana understood it,

the Line of Interval guided you to the weakest point in an object's structure.

And if an object was moving, the Line of Interval's endpoint wouldn't stay in the same place. Its path would keep changing, too.

But given the strength of the boulder in front of him, even though Tachibana could sense the Line of Interval, he wasn't confident he could cut through it.

Kujo Tachibana thought there were only two ways to split the boulder.

First, learn a Breathing Style, improve his physical abilities and explosive power, and cut through it.

But if he didn't travel far, he wouldn't find the Demon Slayer Corps. And without finding them, there was no way to learn a Breathing Style.

So Tachibana could only rely on the second option.

That was to keep studying the Line of Interval and develop the power of Sword Heart Clarity, allowing him to observe the structure of objects on a deeper level.

Take a house, for example. The easiest way to demolish it was to damage its structural supports, causing it to collapse on its own.

The load-bearing walls, the support columns, and so on.

But Kujo Tachibana's problem was that he could find the load-bearing walls, but he couldn't smash them!

So what could he do?

Kujo Tachibana had an idea!

Find the "load-bearing wall" of the load-bearing wall. Exploit the weakness within the weakness!

Kujo Tachibana: "I'm going to smash the most important brick in your body!"

Of course, it sounded simple. Putting it into practice was another matter.

Another three months later.

"Ha!!!"

A clear ring of steel rang out, and the enormous boulder before Kujo Tachibana was gone.

"Phew..."

Tachibana exhaled a breath of stale air, his face pale. He endured the stabbing pain in his head and slowly sheathed his sword.

Looking at the ground, which was covered in tiny fragments of stone, Kujo Tachibana rubbed his temples and couldn't help remarking,

"I guess that counts as cutting it open, right?"

"That move seems a little too powerful."

"It looks like it uses a lot of mental energy, though. My head's about to explode."

A week later.

After selling the Kujo family's ancestral home, Kujo Tachibana left the small county town where he'd lived for fourteen years, carrying a wooden box just like Tanjiro's and a long, narrow bundle wrapped in cloth.

Actually, Tachibana had a few things to say about selling the family home right after his father died!

It wasn't that he wanted to be an unfilial son. The Kujo family was simply dirt poor!

His father, Kujo Kai, had spent the last of the family's money on his illness. Then came the funeral arrangements. To give his father a proper send-off, Tachibana had already borrowed a lot of money, using the ancestral home as collateral.

On top of that, there were his training and living expenses for the next six months...

So now, alone and far from home, Tachibana was barely better off financially than Tanjiro's family.

Looking at the sun setting beyond the distant mountains, Kujo Tachibana murmured,

"I hear the Demon Slayer Corps offers great benefits."

"I'd better hurry up and find them."