Three days later.
"Hahahahaha!"
Naruto walked out of the valley laughing loudly, went straight to Shinazugawa Sanemi, and said proudly, "I've lasted an hour in the first stage. Hurry up and teach me Wind Breathing sword techniques!"
This kid…
Shinazugawa Sanemi looked at the smug Naruto in front of him and sighed helplessly. He had originally thought Naruto would need at least half a month to complete the first stage of training, but instead, he finished it in just three days.
This kind of talent could no longer be described as high or low—he was simply a monster.
He recalled how long it had taken him to complete this stage himself.
Two months? Three months?
Now he was absolutely certain that Naruto would break the record set by Muichiro Tokito and become a Pillar of the Demon Slayer Corps in an even shorter time.
"Take this."
Shinazugawa Sanemi tossed a regular longsword to Naruto, then picked up his nichirin blade and said, "I'll teach you the first three forms of Wind Breathing sword techniques now."
"Mhm!~"
Naruto caught the sword and asked excitedly, "Shinazugawa Sanemi, is this the nichirin blade that can kill demons?"
"No, it's not."
Shinazugawa shook his head. "This is just a regular sword. A specialized swordsmith will custom-forge a nichirin blade for you. The swordsmith responsible for your blade is already on the way and will arrive in a few days."
"Custom-forged!"
Naruto's eyes lit up instantly, and his mind immediately began imagining what his sword would look like.
"Don't get distracted!"
Seeing Naruto's expression, Shinazugawa Sanemi tapped him on the head with the scabbard. Then he drew his nichirin blade and said in a deep voice, "Watch closely. I'm about to demonstrate the first three forms of Wind Breathing."
"First Form: Dust Whirlwind Cutter!"
Holding the blade with one hand, Shinazugawa Sanemi swung forcefully. A rotating wind blade burst forth, easily carving through the ground.
He immediately shifted his stance and swung again, unleashing four claw-shaped wind blades forward.
"Second Form: Claws-Purifying Wind!"
Next, his gaze sharpened. He swung his blade once more, instantly releasing three wind blades centered around himself.
"Third Form: Clear Storm Wind Tree!"
After demonstrating the three forms, Shinazugawa Sanemi sheathed his blade and looked at Naruto.
"Did you see clearly?"
"Mhm!~"
Naruto nodded repeatedly, drew the longsword in his hand, and imitated Shinazugawa Sanemi's movements.
"Wind Breathing, First Form—Dust Whirlwind Cutter!"
Whoosh!~
A rotating wind blade whistled out from Naruto's sword.
Although the wind blade he produced was only about one-tenth the strength of Shinazugawa Sanemi's demonstration, it still made Shinazugawa Sanemi's eyes widen involuntarily.
Not bad… already about one-tenth of what I can casually release.
Before he could finish evaluating, Naruto frowned in dissatisfaction, tightened his grip, and swung again.
"Wind Breathing, First Form—Dust Whirlwind Cutter!"
The second wind blade was visibly stronger than the first.
This kid…
Shinazugawa Sanemi stopped trying to evaluate him.
This brat couldn't be judged by common sense.
"Wind Breathing, Second Form…"
Naruto continued practicing on his own, completely unaware of Shinazugawa Sanemi's thoughts. In just half a day, he had already mastered the first three sword forms of Wind Breathing—after seeing them demonstrated only once.
It could only be said that Shinazugawa Sanemi's simple, direct teaching style—free of complex theory and focused purely on imitation—perfectly suited Naruto.
If it had been Uzui Tengen's complex breathing techniques, which required understanding musical scores and rhythms, Naruto would probably have been driven mad.
"Alright."
Seeing that Naruto had initially mastered the sword forms, Shinazugawa Sanemi stopped him and said, "You've basically learned the movements. Next comes combination training."
"Go back into the valley and continue practicing sword swings in the first stage's wind zone. Once you can split the wind within three meters around your body, you may proceed to the second stage."
"Oh!~"
Naruto responded enthusiastically and immediately rushed back into the valley, sword in hand, continuing his training amidst the roaring winds.
Three days later—
"Wind Breathing, Third Form: Clear Storm Wind Tree!"
Inside the valley, Naruto swung his sword forcefully. Three wind blades erupted around him, cleanly splitting the howling winds within several meters.
"I split it!"
Feeling the wind around him break apart, Naruto's face lit up with excitement. He continued swinging until every strike could reliably split the surrounding wind by at least three meters.
Only then did he stop.
"Shinazugawa, I did it!"
Naruto rushed out of the valley and proudly declared, "Now every time I swing my sword, I can split the wind around my body!"
"Yes, I saw."
Shinazugawa Sanemi nodded calmly. "Although it took a little time, you've completed the first stage of training."
By now, he had already grown accustomed to Naruto's absurd learning speed.
"Next, we begin the second stage."
Looking at Naruto, he continued, "Being able to split the wind in the first stage means your breathing has entered the Total Concentration state."
"What you must do next is maintain and strengthen this state—until you can sustain Total Concentration at all times."
"At all times?" Naruto asked in surprise.
"That's right. At all times."
Shinazugawa Sanemi nodded solemnly. "Even while sleeping. This is called Total Concentration: Constant. Being able to do this is the minimum requirement to approach the level of a Pillar."
"Only the minimum requirement?"
Naruto couldn't help but look shocked. At the same time, he gained a much clearer understanding of just how terrifying a Pillar's strength truly was.
He was already struggling just to maintain Total Concentration Breathing for one hour each day—yet a Pillar could maintain it constantly, and this was merely the baseline.
However…
This realization only made Naruto look forward to the next stage of training even more.