Chapter Five: The Dual Breathing Style!
『ＲＹＯＮ 』
Enjoy~~~
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The air at the summit of Mount Sagiri was so thin it was almost non-existent. For an ordinary person, simply standing here would be enough to cause dizziness and nausea, as if their lungs were trying to inhale crushed glass instead of oxygen.
Rin stood at the peak, watching the back of Sakonji Urokodaki, who stood like a stone statue overlooking the mountainside shrouded in thick mist. The sun had set some time ago, and total darkness was swallowing the forest below, turning the trees into twisted black fingers.
"Descend the mountain and return to my house at the foot before sunrise."
Urokodaki's instructions were terse, cold, and not open for discussion. He didn't warn Rin about traps. He didn't tell him the way. He simply turned and vanished into the fog with ghostly speed, leaving the ten-year-old boy alone to face the mountain.
Rin took a deep breath, attempting to fill his lungs with the scarce air.
"Alright..." Rin whispered to himself, his eyes glowing with the faint blue light of the System that only he could see. "This is the test Tanjiro took. In the anime, Tanjiro suffered terribly here. He was gasping, stumbling, and falling into pits like he was a magnet for disasters."
Rin gave a mocking side-smile.
"But with all due respect to the original protagonist... I'm not a charcoal seller who has never exercised in his life. I am a 'Player' who spent five years training to kill monsters."
[Status: Active]
[Strength: 35]
[Speed: 42]
[Senses: 38 (Enhanced by Sensing Skill)]
Rin took off.
He wasn't running haphazardly; he was gliding between the trees.
The first step was a test. The ground beneath his feet was riddled with twisted roots and slippery stones. But his balance (Level 15) made him look as if he were dancing on a tightrope.
Whish!
The faint sound of a hidden rope snapping.
Thanks to his enhanced senses, Rin heard the fibers of the rope break before the trap even triggered.
"Right!"
He leaned his body to the right with agility, allowing a massive tree trunk tied to swinging ropes to pass by his ear by mere millimeters, creating a sharp gust of air.
"Primitive..." Rin commented as he continued running without slowing down. "Mechanical traps based on tension and gravity. Effective against beginners, but for me? It's just an obstacle course."
He continued his descent. The traps grew more cunning. Holes camouflaged with leaves, wooden knives flying from the sides, and even boulders that rolled the moment specific planks were stepped on.
But Rin was moving in "Easy Mode" compared to Tanjiro. His lungs, trained for years on long-distance running, did not fail him in the thin air. His explosive muscles allowed him to jump over the pits instead of falling into them.
Halfway down, while avoiding a barrage of bamboo spears, a thought occurred to him.
During all this, Rin was wondering what point in the story he was currently in. If he wanted to save the family of the protagonist, Tanjiro, he had to go to them before the story began.
Rin started calculating dates in his head while jumping over a small waterfall.
"I am ten. Tanjiro started his training at around thirteen. This means I have three years, maybe more, before the main events of the anime begin. Three years..."
After a quick calculation, Rin guessed that Tanjiro was the same age as he was currently. He didn't even realize he had miscalculated.
His emerald eyes widened with a terrifyingly ambitious spark.
"Three years is enough. By the time Tanjiro smells the scent of his first demon, I will have already become a Hashira. I will have paved the way. Maybe... maybe I can save Rengoku and save Tanjiro's family. And maybe I can kill Doma before he touches Shinobu. And of course, marry her... ahem!"
Rin reached the foot of the mountain.
The sun had not yet risen. The sky was still a dark gray, and the stars were beginning to fade.
He had descended in half the estimated time.
Urokodaki's hut was before him, and the door was open.
The old master sat at the entrance, his red Tengu mask hiding his expression, but his body language betrayed a sense of shock. He had not expected the child to return so quickly, and with so few injuries (only a few scratches and a tear in his left sleeve).
"I've returned," Rin said, not even panting, but breathing with an eerie regularity. He bowed respectfully. "Am I accepted?"
Urokodaki looked at him for a long time. Internally, the old man was torn.
This child... he is not like the brave Sabito, nor like the calm Giyu. He is something else.
He is suspiciously "ready." His physical strength and senses exceed his age by light-years.
"Yukihara Rin," Urokodaki said in a deep voice. "I accept you as my student. But know this... the path you have chosen is not paved with roses. It is a road paved with the bones of those who were stronger than you."
At that moment, a familiar sound rang in Rin's head.
Ding!
[Congratulations!]
[Main Quest Completed: The Master's Trial]
[Rating: S (Record Time, Minimal Damage)]
[Rewards:]
* 500 Experience Points.
* Increase in Corps Reputation (Hidden).
* Legendary Skill Box (Random - Breathing Techniques Category).
Rin's heart pounded hard. This was the grand prize. The System would give him a ready-made breathing technique, like a database carved directly into his mind and body.
"Open the box," Rin commanded mentally as he followed Urokodaki into the hut.
A golden roulette wheel appeared before his eyes (invisible to Urokodaki), spinning at a maddening speed.
Names of techniques passed quickly: Flame, Water, Wind, Stone, Insect, Love...
"Please, not Love Breathing, I'll look ridiculous waving a whip..."
The wheel began to slow down.
It passed "Water." It passed "Stone."
And it stopped slowly at a glowing yellow lightning bolt symbol.
[Obtained: Thunder Breathing - Level: Beginner]
[Description: One of the five fundamental breathings. Focuses on channeling power into the legs to produce superhuman explosive speed. Requires high flexibility and explosive strength.]
[Bonus Reward: Immediate mastery of the First Form: Thunderclap and Flash.]
Rin stopped in his tracks in the middle of the room, his eyes wide with awe.
"Thunder?!"
He felt a subtle electric current coursing through his veins, specifically in his leg muscles. It was as if his nervous system had been rewired to become a superconductor. Information on how to breathe, how to contract muscles, how to launch at the speed of sound... it all flowed into his mind in a single second.
"What is it?" Urokodaki asked, noticing Rin's sudden halt.
Rin raised his head, an unhideable wide smile crossing his face.
"Nothing, Master. Just... I feel excited. I feel as if a lightning bolt just struck me."
Urokodaki was teaching him "Water Breathing." And the System had granted him "Thunder Breathing."
Water for defense, fluidity, and adaptability.
Thunder for blitz attacks, lethal speed, and decisive moments.
"I'll be a hybrid," Rin thought crazily. "I'll merge the fluidity of water with the speed of thunder. I'll be a walking thunderstorm."
This was dual breathing!
...
Only one week passed.
Normally, it takes a trainee months to learn the basics of "Total Concentration Breathing." Tanjiro struggled for days just to understand the concept and a year to master it.
But Rin was an anomaly.
Rin was standing under the frozen waterfall, the water hitting his bare shoulders with enough force to break bones. He closed his eyes and listened.
Not to the sound of the water, but to the sound of his body.
The System was acting as a cheat interface. It was showing him precise vital signs.
[Blood Oxygen Level: 85%... 90%...]
[Lung Expansion: Optimal]
"Breathe..." Rin whispered. "Imagine the oxygen flowing into every cell. Not as a gas, but as a liquid. Make it flow like water."
At the same time, he was focusing on his legs. "But keep the nerves taut like a bowstring. Ready to launch like lightning."
He raised his wooden sword.
He didn't make an ordinary move.
His body moved with terrifying fluidity.
"Water Breathing... Fourth Form: Striking Tide."
Swash!
Even though it was a wooden sword, Urokodaki, who was watching from the riverbank, swore he saw a faint trace of blue water following the sword's path.
The sword movement was perfect. The angle, the power, the timing.
It wasn't the movement of a beginner trying to imitate. It was the movement of a swordsman who understood "Water."
But Rin didn't stop.
As soon as the water movement ended, his stance shifted suddenly. He leaned forward, placing his hand on the hilt of his imaginary sword, his right leg pressing onto the rock beneath him with such force that it cracked.
The air around him began to vibrate with a low humming sound. Bzzzt.
"What is he doing?" Urokodaki's eyes narrowed behind the mask. "That stance..."
"Thunder... Breathing," Rin whispered inaudibly.
He didn't release the technique fully (since he didn't have a real sword and might break his legs if he erred), but he executed the "Launch."
Boom!
Rin vanished from under the waterfall.
In a fraction of a second, he was standing behind Urokodaki on the bank, water dripping from his long hair, his wooden sword pointed toward a tree trunk, having pierced it ten centimeters deep with a single thrusting strike.
Silence reigned. Only the sound of the waterfall and distant birds.
Urokodaki turned slowly to look at the boy.
Rin was panting slightly, steam rising from his hot body into the cold air. He turned to his master and smiled that smile that was simultaneously innocent and dangerous.
"How was that, Master? Has my breathing improved?"
Urokodaki felt a shiver he hadn't felt in years. Not since he was a Hashira fighting Lower Moons.
This boy... in one week, he mastered the basics of Water Breathing, and somehow, showed flashes of an entirely different style.
"Rin..." Urokodaki said, his voice carrying a terrifying gravity. "Who taught you that second stance?"
"I saw it in a dream," Rin lied smoothly, wiping his face. "I dreamed of an old man wearing a yellow coat who shouted a lot, and he was very fast. I just tried to imitate the feeling of speed." (An allusion to a character... who knows him?)
Urokodaki didn't believe the story entirely, but he believed the result. Talent does not lie.
Urokodaki walked toward Rin and placed his heavy hand on the boy's shoulder.
"You are not Giyu. And you are not Sabito."
He squeezed his shoulder hard.
"You are a little monster, Rin. If you continue at this rate, you won't just become a Demon Slayer."
Urokodaki looked toward the horizon, where demons hide in the darkness.
"You possess the potential to kill an Upper Moon. Perhaps... perhaps even Kibutsuji Muzan himself might find a rival in you one day."
Rin's eyes widened. Gaining recognition from the Hashira trainer this quickly?
But Urokodaki wasn't finished.
"However..."
Urokodaki's tone changed. It became harsher, more brutal.
"Because you have this talent, I cannot train you like the others. Ordinary training won't bring out your potential. It will make you lazy."
Urokodaki pulled a real sword (katana) from beneath his robe and threw it at Rin's feet.
"From now on, the training is over. The hell begins."
He pointed toward the mountain again.
"You won't descend the mountain once a day. You will descend it ten times. And you will carry this sword. And I will be the one chasing you myself this time, and I won't use wooden traps..."
The red mask glinted with a frightening spark.
"I will use the sword. If you don't parry, you will die. Do you understand?"
Rin looked at the real sword at his feet, then at his master who had suddenly turned into a "Final Boss."
Instead of fear, Rin felt excitement. Adrenaline pumped through his veins.
This is what he wanted. Not safe training. But a real fight to forge him.
He picked up the sword, feeling its familiar and comfortable weight.
"Ten times? And a chase with a real sword?"
Rin looked up, his emerald eyes burning with challenge.
"Master... I was afraid you were going to be easy on me because I'm a child. Thank you for not doing so."
The two stood face to face, a legendary master and a prodigy student, both realizing that what would happen in the coming months on Mount Sagiri wouldn't be mere training.
It would be the forging of the most dangerous swordsman the Taisho era would ever witness.
[New Quest: Survival from Hell]
[Difficulty: Nightmare]
[Reward: ???]
Rin smiled.
"Let's dance, Master."
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Chapter Five Ends.