Demon Slayer: My breathing technique went awry after Nezuko pushed me down.

He's handsome, that's all that matters!

Compared to the curved and slender samurai sword, the straight-bladed long sword left by our ancestors is more in line with Shirakawa Yu's aesthetic.

I wonder if this knife can change color depending on the user's physique and breathing technique.

Give it a try!

With one hand gripping the hilt of the sword, holding it upright in front of his chest, Shirakawa Yu took a deep breath—Breath of Color, activated!

The next second, a faint pink hue slowly rose from the tip of the blade, combining with the snow-white and bright body to create a slightly purplish-pink blade.

eerie, mysterious...

So cool!

Shirakawa Yu narrowed his eyes as he watched.

A dignified and solemn knife design, paired with a flamboyant purple-pink blade...

I love it so much~~~~

That's not all!

As the system's first reward, and as the most important partner who will accompany Shirakawa Yu throughout his life.

This knife is certainly not that simple.

According to the system, this knife will awaken a special ability based on the host's awakened breathing technique.

Or rather, traits.

If the host is a water-breathing being, this knife's special qualities might be its exceptional resilience and versatility, capable of being as soft as water or as sharp as ice.

If it's the Breath of Fire, then perhaps the slashes would carry a burning, scorching heat, like half a crimson blade.

Breath of Thunder, Paralyzing Lightning Strike?

Does the respiration of insects inherently carry poison?

Shirakawa Yu didn't know the specifics.

What he was truly certain of was that the characteristic of his Color Breathing was—

Nourish the soul!

Chapter 9 The Purple-Pink Tang Blade!

"Nourish the soul..."

Shirakawa Yu gripped the purplish-pink Tang-style horizontal sword in his hand, feeling the cool touch of the blade and the strange connection that subtly resonated with his own breathing technique.

The system didn't explain exactly how to 'raise' it...

It only mentioned the origin of the knife, without explaining its specific effects, leaving the message that the host should explore it on their own.

The improvement of the Breath of Color lies in the number and strength of the women around him.

Knives are not gender-specific and can offer limited help, but...

Soul Blade is good!

This is why the ability to nourish the soul came into being.

According to Bai Chuanyu's understanding, "nourishing the soul" should mean capturing a woman's soul and transferring it into the sword to keep her company day and night.

In this way, even if there are no other members of the opposite sex around, one should still be able to gain a certain degree of strength boost by relying on the soul of a member of the opposite sex within the sword.

However, whether it is actually as one imagines remains to be seen and will require further investigation.

His gaze involuntarily drifted to Nezuko, who was fast asleep inside the house.

But the next second, he quickly shook his head; he wanted Nezuko to stay with him day and night.

But it's definitely not just about having a soul~

If we're really talking about just the soul...

Bai Chuanyu suddenly froze for a moment, then looked up sharply at the mountaintop!

Oh yeah, I almost forgot about that girl!

If we're really talking about nurturing the soul, or to put it another way, the spirit of the blade!

Isn't there a poor, homeless little girl living on this mountain?!

Shirakawa Yu slapped his thigh!

This has potential!

Just as he was happily examining his new toy, the door to the cabin was gently pulled open.

Urokodaki Sakonji, wearing a tengu mask, walked in silently.

He first glanced at Nezuko, who was sleeping soundly in the corner and whose clothes were neat, then glanced at Shirakawa Yu, who was sitting properly not far away, and nodded almost imperceptibly.

(Fortunately, although this kid is a womanizer, he at least knows his limits and has a bottom line.)

His gaze then fell on the straight longsword in Shirakawa Yu's hand.

The eyes beneath the urn-shaped mask narrowed.

As a former Water Pillar, he had seen no fewer than dozens of Nichirin Blades.

Although the swordsmiths of the Demon Slayer Corps each have their own style, their general designs are consistent.

The blade has a beautifully curved shape, perfect for chopping.

But this one in front of me...

Too straightforward.

From the tsuba (handguard) to the end of the scabbard, it is almost a straight line. The scabbard is also slightly wider than that of a typical Nichirin sword, exuding a simple yet rugged quality.

"This knife."

Urokodaki spoke, but his voice was devoid of emotion.

"Huh? Oh! This!" Shirakawa Yu seemed to only then notice his sword, hurriedly unfastening it and presenting it to Urokodaki with both hands, his actions carrying a hint of "presenting a treasure".

"Master, look! This was passed down in my family!"

Urokodaki didn't take it, but gestured with his eyes for him to pull it out.

"Chong-"

The clear, resonant sound of the sword being drawn was exceptionally distinct in the quiet room.

The moment the blade was completely slung from its sheath, the setting sun shone precisely on the edge—

Bright and clear.

It wasn't the gleaming edge of a samurai sword with its elegant curves, but rather like a straight slice of moonlight, crisp and clean.

Urokodaki's pupils contracted slightly.

This form...

Tang style?

He had seen similar knives before.

Decades ago, there was a swordsman in the Demon Slayer Corps who used a straight-bladed sword. It was said that his ancestors came from the other side of the sea.

But that person's knife wasn't quite so... pure.

"Master? How is it?"

Shirakawa Yu's voice pulled him back to reality.

Urokodaki raised his eyes and looked at Shirakawa Yu's face.

The most crucial element is the color of the blade at this moment.

"...Is this a Nichirin Blade?"

Urokodaki took two steps closer and carefully examined the faint, seemingly flowing purplish-pink luster on the blade.

It is common knowledge that the color of a Nichirin Blade changes according to the user's breathing technique.

"Did any of your ancestors include members of the Demon Slayer Corps?"

Shirakawa Yu shook his head so hard his hair was practically flying, and his expression changed to that of an "honest farmer's son".

"I'm a farmer~"

“This knife was found by my great-great-grandfather in the mountains. My father told me that the snow was particularly heavy that year, and my great-great-grandfather went up the mountain to chop firewood and found it in a cave.”

He paused, lowering his voice, which carried a hint of mystery.

“Ordinary families have never seen such a fine knife before. My great-great-grandfather couldn’t bear to throw it away, but he was also timid and afraid of getting into trouble, so he kept it at home as a family heirloom.”

After he finished speaking, he nodded vigorously, as if to reinforce his credibility.

He wouldn't dare to claim the Demon Slayer Corps as their ancestor so casually.

The Ubuyashiki area has detailed records of all the team members from previous generations; checking them would expose the inconsistency.

This explanation is now perfect! Its origin is unknown! It was found by a dead person! There's no way to verify it!

I'm such a clever little devil!

Urokodaki paused for a moment, seemingly accepting the explanation.

After all, the Demon Slayer Corps has always had a frighteningly high mortality rate, so it's not uncommon for them to lose their swords.

He just glanced at that flamboyant purplish-pink color a couple more times.

This color... a straight and sturdy Tang-style sword paired with a pinkish color that's almost adorable...

The visual impact is quite strong.

"come out."

Urokodaki shook his head, turned and walked outside, "Prepare for training."

"Eh? I have to be scolded too?" Shirakawa Yu pointed to his own nose, but still obediently followed, casually putting the knife on his waist.