Am I Not a System Stream Protagonist but a Mortal Stream Protagonist

The sky was dim, the moon shrouded by dark clouds, and Peach Mountain was pitch black. Only a faint light could be seen on the mountainside. Inside a simple wooden cabin, the dim oil lamp flickered. Yu Luo and Jigoro Kuwajima sat opposite each other, their shadows cast upon the wall.

"I heard from the Stone Pillar that you've fought Oni. So, you've already witnessed their power, haven't you?" Jigoro Kuwajima sat upright. Despite his short stature, he exuded an inexplicable aura of authority, making Yu Luo serious and completely unable to be flippant.

"That's right," Yu Luo said with a grave expression. "Even though it was just the lowest-level Oni that couldn't even speak, its strength was already beyond what a normal person could reach."

"Yes, so to fight these inhuman Oni, the first Demon Slayers developed Breathing Styles, allowing us to possess the strength to fight them."

"Breathing Styles?"

"The human body has a self-preservation mechanism. Under normal circumstances, only a small portion of the body's muscles are used. Breathing Styles, through respiration, fill all the muscles with oxygen, thereby awakening all of them."

Jigoro Kuwajima explained to Yu Luo, who suddenly understood and then had new questions:

"But Oni are immortal. Ripples... no, do Breathing Styles have the ability to kill Oni?"

If so, would there be Stand Users?

Of course, Yu Luo only thought this in his mind, not daring to say it aloud. This old man was very stubborn, and he had been lectured for a long time for just a few casual remarks. He could only complain in his heart.

"Demon Slayers have special swords called Nichirin Blades. Any Oni whose neck is severed by a Nichirin Blade will die instantly," Jigoro Kuwajima said calmly. "When you join the Demon Slayer Corps in the future, there will be a dedicated swordsmith to forge a sword for you."

"Next, I will teach you about Breathing Styles. Breathing Styles are divided into five fundamental styles: Water Breathing, Flame Breathing, Wind Breathing, Thunder Breathing, and Stone Breathing."

"Then there are Breathing Styles that branch off from the fundamental ones. The Sound Breathing that I use is a branch of Thunder Breathing."

"So, old man, are you planning to teach me Sound Breathing?"

"No, I am teaching you Thunder Breathing." Jigoro Kuwajima looked at Yu Luo with piercing eyes, then imparted all the key points and methods of Thunder Breathing.

It had to be said that although the old man always seemed to look down on Yu Luo, even showing disdain, he was not only meticulously explaining all the key points of Thunder Breathing but also quite attentive. After explaining each part, he would ask Yu Luo if he understood and even demonstrate it himself. This greatly changed Yu Luo's perception of him.

It seems the old man is only fierce with his words; he's actually quite warm-hearted. Such a tsundere! Yu Luo muttered inwardly, never daring to say it out loud.

At dawn, the sky was just beginning to lighten, and a thin mist permeated Peach Mountain. Yu Luo, still in a deep sleep, was startled awake by a sudden chill. His sleepiness vanished instantly, and he shot out of bed, looking around, still confused about what had happened.

Jigoro Kuwajima, holding a gourd ladle and leaning on his cane, puffed out his cheeks and glared, then sternly ordered Yu Luo:

"First, air out your futon. Then, chop all the firewood behind the house. Fill the water jar. If you don't finish, you won't have lunch."

"How can any human possibly wake up at six in the morning!" Yu Luo exclaimed in despair, uttering a famous quote. In response, he received an unceremonious whack on his backside with the cane.

"Less nonsense!!!" With that, Jigoro Kuwajima glared at Yu Luo and walked straight out. Just like yesterday, he didn't say where he was going, leaving Yu Luo looking utterly dejected at the wet bed, reluctantly carrying all the damp bedding outside to dry.

"Huh? Host, did you wet the bed?!" The System in his mind suddenly asked with feigned surprise, clearly trying to suppress its laughter.

Yu Luo glanced at the wet patch on the futon, his face immediately darkening. He snorted coldly, picked up the axe that gleamed with a cold light, and went behind the house. The firewood he had chopped yesterday had disappeared, replaced by a new pile of wood that was as tall as a person.

By the time he finally finished chopping the firewood, the sun was already high in the sky. Yu Luo's thin kimono was completely soaked with sweat, clinging tightly to his body. He looked up at the sky. Without giving him any time to rest, he picked up the empty water buckets with his sore, weak hands and headed down the mountain.

There was no water source on the mountain; he had to fetch water from the small stream at the foot of the mountain. Yu Luo was a shut-in, his stamina even less than that of a normal person. He might even have less stamina than the peasant women in this world. He had never done such strenuous labor before. Walking on the mountain path, he felt as if he might fall at any moment. There were many times he thought about resting or even running away and giving up on joining the Demon Slayer Corps.

However, every time such a thought crossed his mind, the image of those mutilated corpses and the Butterfly sisters would appear in his heart, making Yu Luo grit his teeth and persevere through the soreness and discomfort all over his body.

"Splash..." Yu Luo accidentally stepped on a loose stone, losing his balance. The two heavy water buckets on his shoulders flew off, rolling far down the mountain path. His kimono was covered in dirt.

On a treetop not far away, Jigoro Kuwajima stood silently, watching Yu Luo below slowly get up from the ground, retrieve the two buckets, and turn to limp down the mountain to fetch water from the stream again.

"He talks too much, but he has some perseverance. He's qualified," Jigoro Kuwajima softly commented on Yu Luo, then disappeared from the branch in the blink of an eye.

By the time Yu Luo finished chopping firewood and filled the water vat, it was already past 2 PM. Numbly pouring the last bucket of water into the water vat, Jigoro Kuwajima stopped Yu Luo from picking up the buckets again:

"Alright, go rest for a bit. There's still something to do later."

Hearing Jigoro Kuwajima's words, Yu Luo turned his stiff head to look at him, then collapsed to the ground as if his backbone had been removed. His dirty clothes made intimate contact with the ground, his eyes staring blankly at the blue sky dotted with white clouds, his mind a complete blank.

After a long while, Yu Luo slowly came back to his senses. The soreness all over his body surged into his mind, like ant bites, making Yu Luo grimace in discomfort.

Enduring the discomfort of his muscles, Yu Luo bent over and shuffled into the simple wooden cabin. Jigoro Kuwajima was nowhere to be seen, but Yu Luo wasn't looking for him. He walked directly towards the kitchen. However, the kitchen was spotless, and the bowls and chopsticks were neatly placed in the cupboard. It seemed Jigoro Kuwajima's words about not having food were not empty threats.

Yu Luo searched the kitchen unwillingly, lifting the lid of a pot. Inside, he found two small bowls: one with rice and one with miso soup, still emitting a faint warmth.

"As expected!" Yu Luo exclaimed with joy, taking out the food. He wolfed it down. He hadn't eaten anything since waking up in the morning, and his stomach was already empty. As he ate, he thought:

The old man really is all bark and no bite.

He said there would be no food, but he still left his portion and even warmed it up for him, completely unlike his stern demeanor.

"Are you done eating?" Jigoro Kuwajima reappeared before Yu Luo, asking him as he was wolfing down his food.

Yu Luo looked at the elusive Jigoro Kuwajima. Although his face remained expressionless, Yu Luo's mood relaxed considerably. He replied with a smile, "Almost, almost."

"Here!" The old man tossed the item in his right hand to Yu Luo. Yu Luo put down his bowl and chopsticks and took it. It was a Katana.

"This?" Yu Luo asked, puzzled.

"This is a sword I used before. Although it's not a Nichirin Blade, it's enough for you at the moment," Jigoro Kuwajima explained calmly to Yu Luo's confusion. "After you rest, go practice your sword swings. 3,000 times!"

"Um, I..."

"If you don't finish, don't even think about sleeping!!" Jigoro Kuwajima, thinking Yu Luo wanted to bargain, interrupted him sternly.

Yu Luo looked at Jigoro Kuwajima's retreating back with an innocent expression and muttered softly, "But I have a sword."