Igarashi Uzen was neither mistaken nor joking.
Blowing into gourds, death-matches underwater, or bitter cultivation on high plateaus... those methods were about creating extreme environments to force the body to adapt to a high-efficiency state and integrate it into a swordsman's daily life.
But the method he intended to teach Kuguruma Natsunishi was different. It was about integration; it was about life.
"Imagine," the Storm Hashira said, picking up his coffee. His tone was as peaceful as the slight ripples in his cup. "It isn't about 'occasionally becoming a superhuman,' but rather letting the 'superhuman' learn how to eat, sleep, and drink coffee like an ordinary person. Without wasting a single shred of extra energy, maintaining a heart as calm as usual. That is what I want you to do. Do not try to 'maintain' Total Concentration; instead, make Total Concentration 'disappear.' Forget that it is a technique of a Breathing Style and let it return to its essence: the simple act of breathing."
Kuguruma Natsunishi scratched his head. Why did this sound like some mystical plot point from an old manga?
He spoke up, "Then, Senior Aizen, should I start by making coffee? What exactly do I need to do?"
He then watched as Igarashi silently handed him a glass jar from his side. It was filled with coffee beans.
Kuguruma Natsunishi: ≖_≖
Senior, you aren't just using my training as an excuse to get free labor for your coffee, are you?
Facing the youth's blatant skepticism, Igarashi merely cleared his throat, his expression serious. "This is part of the cultivation."
And so, from that day on, a new figure appeared in Igarashi's estate and even in several coffee shops owned by the Igarashi family in Yokohama. He maintained Total Concentration while grinding beans, extracting, and brewing.
It was much harder than Kuguruma Natsunishi had imagined. After a long period, his lungs felt like they were on fire, and he simply couldn't maintain Total Concentration. Even when he managed to stabilize it for a moment... the second his mind focused slightly on his breathing, the strength in his hands would suddenly explode, just as it did in battle. Either the hand grinder would be twisted into pieces, or he would press the coffee grounds directly into a hard puck while leveling them.
"Don't let the lightning roar. You must control it, learn to let the thunder brew silently within the clouds," Igarashi said without looking up from the book he was reading nearby. "Thunder Breathing doesn't always have to be vented immediately. Feel the aroma of the beans more, relax. Don't try to fight your breath; regulate your breathing rhythm peacefully."
Crack.
Distracted, Kuguruma Natsunishi pressed down with his palm and collapsed a large section of the solid wood workbench. The shop manager and staff nearby were so startled they scrambled back several steps.
Kuguruma Natsunishi: ...
Igarashi: ...
It seemed his junior was finally acting like a normal person during this stage of training. A trace of almost mischievous amusement flickered across the Storm Hashira's face. It was lucky the Igarashi family was wealthy enough to withstand such destruction. If it were an ordinary coffee shop, this apprentice with terrifying destructive power would have been kicked out long ago.
Naturally, Kuguruma Natsunishi's training extended far beyond coffee. On the third day, he was taken to the banks of the Ooka River. This time, he was tasked with sinking his heart into fishing while maintaining Total Concentration.
It was even harder than grinding coffee. Under Total Concentration, the high state of excitement brought by Thunder Breathing and the extreme mental stillness required for fishing were at two opposite poles. Kuguruma Natsunishi felt like an overclocked engine being forced to perform micro-engraving. The result, naturally, was ripples constantly spreading across the water, scaring away the fish countless times.
He spent the entire day as a "Air Force" veteran—catching nothing but air.
Starting from the fifth day, Igarashi arranged for Kuguruma Natsunishi to go to the Yokohama Library. He handed him a thick volume of philosophy. The requirement was to maintain Total Concentration while flipping through the book, reading, understanding, and taking notes.
Kuguruma Natsunishi felt his temples throbbing. How was he supposed to read this?! With his brain and body operating at high speed and in constant agitation, even flipping a page steadily was a struggle. The power that was constantly exploding and being reined back in made his entire body tremble. He even felt as if the words on the page were trying to break free and dance before his eyes... let alone actually absorbing the content.
And it was a damn philosophy book. Kuguruma Natsunishi had no doubt that even if he were holding a lewd novel, he wouldn't be able to process a single word right now. He glanced toward the window at Igarashi, who was leisurely gazing at the street scenery.
This senior... this bastard is definitely laughing! He's absolutely laughing at me!
...
By the time Sashiko returned to Yokohama after completing her mission, she witnessed a strange sight. Kuguruma Natsunishi was in Igarashi's courtyard, his whole body trembling as he watered the flowers and plants. He looked as if he were suffering a great grievance but was forced to endure it. She even saw the stream of water from the watering can splitting into several fine, scattered lines because of the tremors in Kuguruma Natsunishi's right hand.
"Um... what is Kuguruma Natsunishi-kun doing?" she couldn't help but ask the other two swordsmen who had returned a few days earlier.
Kondo, whose rank was lower than Sashiko's, was naturally bewildered. On the contrary, Dojima, who was close to being promoted to Tsuchinoto rank, knew a little. "This... is likely the training for Total Concentration: Constant."
The two Water Breathing users looked blank. Dojima had no choice but to briefly explain the concept of "Constant" to them.
"So amazing, is Senior already working toward becoming a Hashira?" Kondo exclaimed.
Dojima was somewhat speechless at Kondo's denseness: How can the Tsuguko-sama be seen as anything other than a Hashira candidate?
Meanwhile, Sashiko widened her eyes, watching Kuguruma Natsunishi intently. Kuguruma Natsunishi-kun... he really has never stopped moving forward.
The three had their own thoughts, but none of them anticipated what would happen next. The difficulty of their sparring sessions suddenly skyrocketed. Because now, Kuguruma Natsunishi had become extremely clumsy at "holding back" and "guiding" during their training. He could no longer control his strength with the ease he once had. Every block, every dodge, and every counterattack carried the full-power operation of his "Constant" state—near-instinctual speed and monstrous strength.
To him, it was a light tap. To the three apprentices, it was a heavy blow that required everything they had to withstand.
After Kuguruma Natsunishi used a near-prophetic footwork to dodge an attack once more and returned a highly exaggerated counter, Kondo was the first to give out. Clutching his struck abdomen, he fell to the ground and lost consciousness.
Yukiziri Sashiko gritted her teeth, her body covered in bruises and her eyes slightly red from overexertion. Because Dojima was stronger, he still had some stamina left, but he could only lean silently on his sword. Sweat had long since soaked through his heavy training uniform.
Sashiko panted heavily, speaking in fragments. "Kuguruma Natsunishi-kun, your strength is just too much... I'm about to... give in..."
Despite feeling that she had made significant progress over these days, she now found herself back in a position where she could hardly handle two or three casual moves from him. Even though she knew Kuguruma Natsunishi was trying his best to hold back, the massive force constantly pressing down on her like a tide made her feel so suffocated she couldn't even resist. She couldn't even catch her breath.
Dojima was equally disheveled. "It's not just the strength; his skill and awareness are far beyond ours to begin with... Let alone you, Yukiziri, even I can't take much more of this."
Kuguruma Natsunishi looked at the two with some apology. He had originally intended not to use "Constant" while training the three of them. Unfortunately, his senior had insisted that this was a necessary part of his own cultivation—that even in combat, he had to integrate it into his training. Otherwise, why would he use such methods on Sashiko and the others? Was he that kind of person?
Kuguruma Natsunishi glanced at his system panel. The progress of Thunder Breathing was moving forward at an unprecedented speed. It was far faster than his solo sword practice or meditation, and swifter than the previous days spent grinding coffee, fishing, or reading philosophy.
Sorry, Sashiko, Dojima, and Kondo. I'll have to trouble you for a while. If you must blame someone, blame the wicked Igarashi Uzen. The training plan was set by the Storm Hashira himself.
Kuguruma Natsunishi clenched his fists again and took a step toward the two who were still barely standing.
In the attic, Igarashi, who was drinking coffee and enjoying a pleasant moment of downtime, suddenly felt his brow twitch. Why did he just get the feeling... that someone was talking bad about him?