Demon Slayer: Start With Heroic Spirit Legacy System

The next morning, as dawn broke, Zhou Yi was already waiting outside the door when Urokodaki stepped out.

The air at the foot of the mountain was damp, and Zhou Yi's clothes were soaked with dew, evidence that he had been waiting for a long time.

Urokodaki nodded in satisfaction.

"The morning is the best time to start the day. Your dedication to training pleases me!"

---

Before long, the two made their way into the misty Mount Sagiri.

The Demon Slayer Corps has existed for over a thousand years.

In its early days, demons were slain using Nichirin Blades, weapons forged from scarlet crimson iron. 

This rare mineral, found in the mountains, absorbs sunlight year-round, making it a natural nemesis of demons.

Later, the development of Breathing Techniques emerged.

The five foundational styles are Wind, Thunder, Water, Stone, and Flame.

Mastering these techniques greatly enhances the ability to eliminate demons.

The Corps consists not only of Demon Slayers but also Kakushi, who handle cleanup, and Cultivators, who train and recruit fresh blood.

Most Cultivators are elderly, retired warriors of exceptional strength.

Among them, Urokodaki Sakonji is not only a Cultivator but also a former Water Hashira, specializing in the Water Breathing technique.

Urokodaki explained everything thoroughly, and Zhou Yi listened attentively.

In fact, Zhou Yi knew even more—about the lost Sun Breathing technique, the identities of the Upper Moons, and more.

However, it wasn't the right time to reveal this knowledge, so he kept it to himself.

"Here, use this sword for now."

Urokodaki tossed a Nichirin Blade to Zhou Yi.

"This is a Nichirin Blade!" Zhou Yi's eyes lit up as he caught it.

The moment his hand gripped the blade, Zhou Yi felt an endless surge of power coursing through his body!

This was the effect of Sasaki Kojiro's inheritance activating!

Eager to test it out, Zhou Yi drew the blade and made a few simple swings.

Urokodaki didn't reprimand him; in his eyes, such enthusiasm upon receiving a new weapon was perfectly normal.

"That's right. Today, I'll teach you some basic sword techniques and the fundamentals of Water Breathing."

With that, he began demonstrating Water Breathing techniques.

"Pay attention! This is the first form!"

"Water Breathing, First Form: Water Surface Slash!"

Urokodaki swung his blade horizontally at a nearby tree.

Swish!

In an instant, the massive tree—large enough to require an adult to wrap their arms around—was cleanly sliced in half.

Though the slash wasn't particularly fast, in Zhou Yi's eyes, it played out in slow motion.

The way the muscles worked, the stance of the feet, even the rhythm of the breathing—all of it was broken down in his mind, replaying over and over.

"This feeling… I think I've got it!"

Zhou Yi was thrilled.

Ding! Observed advanced swordsmanship. Sasaki Kojiro's inheritance progress has reached 1%.

Observing more refined sword techniques can unlock further inheritance progress.

The system notification sounded in his mind.

The mountain was steep and towering.

Upon reaching the summit, the air was noticeably thin.

Yet Zhou Yi remained unaffected. His face was flushed with health, and his breathing was steady.

Urokodaki silently nodded in approval.

As expected, he hadn't chosen wrong. Zhou Yi had excellent physical fitness!

A strong body combined with an exceptional mindset—he was undoubtedly a promising candidate for slaying demons.

"Next, I'll teach you the basics of the Demon Slayer Corps and how to use sword techniques to exterminate demons."

"Understood, Master."

"Great! This way, I'll learn even faster!"

Zhou Yi's excitement was clearly visible, and Urokodaki Sakonji couldn't help but notice it. He assumed the boy was captivated by his swordsmanship, and a sense of pride welled up within him. With a chuckle, he said:

"Haha, you'll reach this level someday too!"

"But the techniques of Water Breathing must be paired with proper breathing methods; otherwise, they can't be—"

Before Urokodaki could finish speaking, Zhou Yi was already mimicking the moves.

"Water Breathing, First Form: Water Surface Slash!"

His movements were remarkably accurate! 

Although there were slight differences from Urokodaki's execution, it was impressively close.

Urokodaki was stunned. To be able to imitate this skill so closely after just watching it once… This boy's potential was boundless—perhaps even equal to or surpassing his own!

"Still, as I said, without the breathing method, you won't be able to fully execute the technique."

What happened next nearly made Urokodaki's jaw drop.

Zhou Yi slightly opened his mouth and took a deep breath.

The sparse air around them suddenly rushed toward him like a tidal wave!

"This! This is the Breathing Technique!"

"And not just that—it's Total Concentration Breathing! Rapidly absorbing oxygen to enhance the body's functions in a short time!"

"But I never taught him the breathing method?"

"Could it be? He learned it just by watching me?"

"And even grasped Total Concentration Breathing!"

Urokodaki was at a loss for words. Thankfully, the tengu mask on his face preserved the last shred of his dignity as a teacher, hiding his momentary loss of composure from his student.

Boom!

With a swing of Zhou Yi's blade, a thicker tree nearby was cleanly felled, crashing to the ground with a loud thud and kicking up a cloud of dust.

"Wait! Zhou Yi's posture is better suited for the physique of someone his age!"

"Not only does it allow for greater force, but it also reduces the strain on the body!"

"Is he really just a kid?"

Urokodaki stared at Zhou Yi, his gaze filled with disbelief. If he hadn't witnessed it himself, he wouldn't have believed what had just happened.

Meanwhile, Zhou Yi, brimming with excitement, turned to look at his master with a bright smile.

"How was it, Master? I did pretty well, right?"

"N-not bad... quite good... about the same as I was when I first started..."

Master's dignity compelled him to utter these begrudging words.

Ding! The host has executed a flawless slash! Progress in Sasaki Kojiro's inheritance has reached 2%!

Zhou Yi felt an even deeper connection to the Nichirin blade in his hand, and his mind was flooded with countless sword techniques.

Practice makes perfect! He loved this feeling!

Unable to contain his excitement, Zhou Yi eagerly shouted to Urokodaki Sakonji: "Master! Teach me the next move!"

Urokodaki composed himself, taking a moment to regain his calm.

"Although you've done well, training must be done step by step. Avoid arrogance and impatience."

Fearing his student might become overconfident, he offered this piece of advice.

"In a boat sailing against the current, not advancing is falling behind. Master, I can do it," Zhou Yi declared with determination shining in his eyes.

Seeing his disciple's drive, Urokodaki couldn't say much more.

"Alright then, let me show you a few more moves."

"Water Breathing, Second Form: Water Wheel!"

"Master, is it like this?"

Once again, Zhou Yi effortlessly executed the technique just demonstrated, but with even greater power and less energy consumption!

Unwilling to concede, Urokodaki moved on to the next move.

"Water Breathing, Third Form: Flowing Dance!"

"Master, I've got it! And I think this move can be performed with a hum—look!"

Zhou Yi performed Water Breathing, Third Form: Flowing Dance again. 

Not only was it perfect, but it was also smoother than before!

"This is absurd!"

"Try this move next!"

…

And so, Urokodaki kept demonstrating, while Zhou Yi flawlessly replicated each move he saw.

Before long, Zhou Yi had mastered every Water Breathing form except the Tenth.

Urokodaki swallowed hard, his expression numb.

"This is the last move. If you manage to learn this one too, I might just…"

"I might just need to seriously reconsider how I teach you."

With one last show of stubbornness, Urokodaki resolved not to embarrass himself.

Taking a deep breath, his aged body erupted with an astonishing surge of power!

"Watch closely! This is the ultimate technique of Water Breathing!"

"Water Breathing, Tenth Form: Constant Flux!"

His movements resembled a coiling dragon, twisting and turning with agile precision. With each rotation, the power of the technique intensified.

With a single slash, a gale-like force erupted!

The surrounding trees were uprooted and sent flying!

Urokodaki was left gasping for air. 

Old age had made using such a technique increasingly taxing.

He looked at Zhou Yi, whose eyes were wide with awe and excitement, his mouth agape, and nodded in satisfaction.

"What do you think? Impressive, right? This is the most difficult technique to learn. It's perfectly normal if you can't perform it after just seeing it once! Don't be discouraged!"

"Master, Master! What an incredible technique! I've already learned it!"

"Yes, I knew it. How could someone possibly learn it just by watching…"

"No worries, you can—"

"What? You said you already mastered it?"

At this moment, Urokodaki's jaw almost hit the floor!

Behind the tengu mask, his face stretched long with disbelief.

You're making me look completely ordinary here!

Can't you give me a little respect?

Right then, the 12-year-old Zhou Yi crouched low, his left foot powering up in an instant.

"Water Breathing, Tenth Form: Constant Flux!"

A flawless spin! A perfect slash!

The already ravaged training ground suffered yet another devastating blow!

Boom!

The blade struck the ground.

Urokodaki could have sworn Mount Sagiri trembled three times.

Left behind on the ground was a massive fissure!

Seeing that he had successfully performed yet another new technique, Zhou Yi was ecstatic! He turned to his stunned master and said.

"Master, how was it? I think I did pretty well, right?"

Urokodaki Sakonji fell into an endless spiral of self-doubt and reflection.

"Ah, yes, yes, absolutely, absolutely!"

"Who am I? Where am I? Why did I even come here?"