The three continued along the mountain path, and small beads of sweat gradually appeared on Tanjiro's forehead.
The bamboo basket carrying Nezuko was not particularly heavy, yet moving without making any sound was extremely difficult. Each of Tanjiro's steps was careful and deliberate. His toes touched the ground first, then his heel slowly followed.
Sakonji Urokodaki moved ahead of them with light steps, occasionally glancing back to observe Tanjiro's progress. Seeing the boy's focused expression and increasingly stable movements, he gave a faint nod beneath his mask.
"Keep your breathing steady," Sakonji reminded quietly.
"Imagine your body flowing like water."
Tanjiro nodded and tried to adjust his breathing.
He noticed that whenever Sakonji exhaled, a faint wisp of white mist drifted out from beneath the Tengu mask, almost as if his breathing had truly merged with the rhythm of water.
Sol Mirek walked behind them with his hands tucked casually into his sleeves. At first glance he looked relaxed and uninterested, but in truth he was carefully observing their movements.
Sakonji's breathing pattern immediately caught his attention.
Each inhale caused the older man's abdomen to expand slightly, while every exhale was long, steady, and controlled.
"So this is the foundation of the Breathing Styles," Sol thought as he memorized the details.
By noon, the three of them reached a small stream and stopped to rest.
Tanjiro gently lowered the bamboo basket and rubbed his aching shoulders.
Inside the basket, Nezuko stirred slightly but remained asleep.
"You did well," Sakonji said as he removed a water bottle from his waist and handed it to Tanjiro.
"But it is far from enough. A true Demon Slayer can run at full speed without making a sound."
Tanjiro accepted the bottle and drank greedily, his throat moving as he swallowed mouthful after mouthful of cool water.
"I will keep working hard, Mr. Sakonji."
Nearby, Sol crouched beside the stream and scooped a handful of clear water into his palm.
Sunlight passed through the gaps between his fingers, scattering small reflections across the surface of the water.
He spoke suddenly.
"This breathing method does more than improve physical strength, right? There are other effects."
Sakonji paused when he heard the question.
He slowly set down his bottle before answering.
"Breathing Styles can awaken human potential and allow a swordsman to gain strength beyond ordinary limits. However, their true power appears when combined with a Nichirin Blade."
Sol nodded slightly while letting the water slip back into the stream.
"If someone used their palm as a blade instead," he said casually, "the result should be similar, correct?"
Tanjiro leaned closer out of curiosity, eager to learn anything he could.
Sakonji hesitated.
No one had ever truly attempted such a thing.
Breathing Styles were designed to work with Nichirin Blades. Only those blades could properly channel the technique and allow demons to be slain.
Still, the thought lingered.
If the human body itself transmitted the force of the technique, then in theory it might work.
Sakonji realized, somewhat belatedly, that Sol had already led his thinking in that direction.
After a moment of consideration, Sakonji slowly nodded.
"In theory it might be possible. However, the special material of a Nichirin Blade remains essential when fighting demons."
Sol smiled faintly.
"Then let's test it."
He stood up and raised his right hand, his fingers straight and pressed together like the edge of a blade.
Sol adjusted his breathing to match the rhythm he had observed earlier.
As he inhaled deeply, the muscles in his arm tightened slightly.
A faint blue glow gathered at his fingertips.
"Water Breathing, First Form, Water Surface Slash."
Before the final word finished leaving his mouth, Sol swung his hand through the air.
A blue ripple spread outward.
The stream in front of him split cleanly in two. The flowing water parted to reveal the pebbles beneath it, remaining separated for several seconds before finally rushing back together.
Sakonji's Tengu mask nearly slipped from his face.
He stared in disbelief.
"How is this possible?"
Tanjiro dropped to his knees in shock, his mouth hanging open.
"Mr. Sol, did you just learn a Breathing Style on your first try?"
Sol lowered his hand and looked satisfied.
"The result is decent. These Breathing Styles are more interesting than I expected."
Sakonji inhaled slowly, trying to calm the shock in his chest.
"When exactly did you learn this?"
"Last night," Sol replied casually. "When we sparred. It did not look that difficult."
In truth, he felt it was far simpler than Bang's Water Stream Rock Smashing Fist.
Sakonji fell silent for a long moment.
Then he suddenly laughed softly, a sound filled with both amazement and resignation.
"Mr. Sol, your talent is beyond anything I have ever seen."
His voice was low and rough with emotion.
"I have practiced Water Breathing for more than forty years, yet I have never witnessed someone grasp its essence during their first attempt."
Sol shrugged casually.
"It's just a small trick."
Tanjiro quickly stood up again, his eyes shining with admiration.
"Mr. Sol is incredible. Can you teach me too?"
"Tanjiro," Sakonji said firmly, "do not rush ahead. Breathing Styles require steady practice. You must begin with the basics."
Sol glanced at Tanjiro's hopeful expression and gave a small smile.
"He's right."
Then he looked toward Sakonji.
"Still, would you mind if I watched while you teach? I might be able to help."
Sakonji hesitated briefly before nodding.
"You may observe. However, please do not interfere with the teaching process."
The group resumed their journey toward Mount Sagiri.
As they climbed higher, the air grew thinner and Tanjiro's breathing gradually became heavier.
Sakonji slowed his pace and began demonstrating the most basic breathing technique.
"Watch my breathing rhythm," he said while placing his hands on his abdomen.
"When you inhale, let the air sink deep into your abdomen. When you exhale, imagine water flowing through every part of your body."
Sol stood quietly to the side and observed.
His eyes moved between Sakonji's breathing rhythm and Tanjiro's awkward attempts to imitate it.
From time to time, Sol stepped forward to make small adjustments.
"No, relax your shoulders a little more."
His finger lightly tapped Tanjiro's tense shoulder.
"Breathing is not about forcing air into your body. Let it move naturally."
Tanjiro followed the advice and adjusted his posture.
Almost immediately the breathing became easier.
His eyes widened in surprise.
"It really works."
Sakonji's eyebrows lifted slightly beneath his mask.
He had to admit that Sol's guidance was extremely precise.
This mysterious young man possessed not only extraordinary talent, but also remarkable insight when guiding others.
If Sol continued observing for only a few more days, Sakonji suspected that every technique he knew would soon be learned.
Teaching such a student was both a blessing and a challenge.
A blessing, because few teachers would ever encounter someone with such talent.
A challenge, because the student might master everything before the teaching had even truly begun, and soon surpass the teacher himself.