"No way, Big Brother!"
Senjuro, who had been standing quietly nearby, couldn't help but speak up. His voice was shrill with panic.
"Absolutely not! Father always said this is our family's Breathing Style and we can't teach it to outsiders!"
At that moment, Senjuro finally understood. He finally knew why his older brother always praised Su Chen so much.
It was because Su Chen was truly terrifying!
He had only fought with Big Brother once, and he had already secretly learned most of his ultimate skill!
If Kyojuro showed him the last move, the Ninth Form, wouldn't Su Chen have stolen everything from the Rengoku family?
Senjuro felt a hot flush of embarrassment and frustration. He, as Big Brother's younger brother, hadn't even learned it yet. How could he let a complete outsider like Su Chen learn it first?
If Su Chen learned it before him, wouldn't it make Senjuro seem incredibly stupid?
So, absolutely not!
Desperate, Senjuro ran forward and tugged hard at Kyojuro's clothes, almost whining like a small child.
Kyojuro, however, remained unmoved by the pulling. He stood tall, his gaze fixed on Su Chen as he weighed the pros and cons of the situation.
What Senjuro said wasn't wrong. Flame Breathing was a Breathing Style unique to the Rengoku family. It was a legacy passed down from father to son for generations. Kyojuro truly felt it was wrong, a break in tradition, to just... teach it to Su Chen, an outsider.
His first idea, to adopt him, had been rejected. Su Chen was unwilling to become his adopted son.
This was a bit of a headache!
However, despite what tradition said, Kyojuro was the current Flame Hashira. The final decision was still in his hands. He had a duty not just to his family's past, but to the future of the entire Demon Slayer Corps.
Suddenly, a thought flashed through Kyojuro's mind.
Why did Su Chen tell me that he had just learned Flame Breathing?
Su Chen could have kept quiet. He could have just watched, learned, and then found an opportunity later to secretly learn the Ninth Form: Purgatory. He could have hidden his new skill.
But he didn't. Su Chen had spoken up.
It showed that he respected Kyojuro. It showed he respected his family's legacy. He was asking for permission, not just stealing the technique.
In that instant, Kyojuro made his decision.
He reached for the hilt of the Nichirin Sword at his waist.
Seeing this action, Senjuro immediately understood what his Big Brother was planning. His breath caught in his throat. Although he didn't quite understand why Big Brother would do this, Senjuro still held onto Kyojuro's hand tightly, a last, desperate plea.
Su Chen and Kanao stood quietly to the side. They knew this was a Rengoku family matter, and they could not interfere. They could only wait silently for the outcome.
Kyojuro looked down at his younger brother. He gently patted Senjuro's head, his expression softening. Then, he spoke, his voice earnest and firm.
"Senjuro, what is the purpose for which Flame Breathing was created?"
Senjuro looked up, confused by the question.
"It was created to slay demons," Kyojuro answered his own question, his voice clear. "As long as this Breathing Style is mastered by someone we approve of, and as long as it's used to slay demons, then it is the right thing to do."
He looked directly at Su Chen, then back to his brother.
"I am the Flame Hashira now, and I approve of Su Chen. That is why I am willing to teach Su Chen Flame Breathing."
Then, his voice grew louder, ringing with absolute conviction. It was a formal declaration, an oath to the world.
"If Su Chen ever betrays the Demon Slayer Corps, or if he ever turns into a demon... I, Kyojuro Rengoku, will commit seppuku to atone for it!"
Kyojuro Rengoku's words were powerful and resonant. The air itself seemed to grow heavy with the weight of his oath.
Everyone present was moved.
Especially Su Chen.
He hadn't expected Kyojuro Rengoku to view this matter with such importance. He hadn't expected the Hashira to stake his own life and honor on him. An indescribable sense of responsibility suddenly weighed heavily on Su Chen's heart.
In the Demon Slayer Corps , the Rengoku family's Breathing Style represented a sacred legacy.
Historically, it had never happened that an outsider learned Flame Breathing.
But today, it had.
Su Chen was the first outsider to be given this honor.
In other words, Senjuro, a member of the Rengoku family, could be said to have witnessed history.
Seeing his Big Brother speak such solemn words, Senjuro silently released Kyojuro's sleeve. His protest was over.
He was not a child who couldn't distinguish between important and unimportant matters.
Kyojuro's words just now were not just for him to hear.
They were an oath.
They represented that Kyojuro Rengoku was the guarantor of this matter. If Senjuro were to stop him again, it would be disrespecting a warrior's dignity and his brother's honor.
So Senjuro could only put away his thoughts.
He stepped back and gave Su Chen one last, resentful glance.
It seems I can't slack off in my training anymore, Senjuro thought, clenching his small fists. I absolutely have to learn Flame Breathing quickly! I have to learn it before Su Chen does!
Kyojuro drew his Nichirin Sword. He silently put some distance between himself and the others, walking to a clear patch of ground.
His arm powered down, and he plunged the red blade into the ground with a soft thud. He faced forward, settling into a low, sideways stance.
Bullet Time!
Su Chen immediately widened his eyes, activating his ability. The world slowed.
He noticed a colorless, shimmering gas emanating from Kyojuro.
This gas was exhaled from Kyojuro's limbs and bones, faintly swirling around him. It gave off an inexplicable, majestic, and overwhelming aura!
Is this... fighting spirit?
Su Chen murmured in his heart. This was the first time he had seen it so clearly.
In Su Chen's enhanced eyes, the fighting spirit on Kyojuro was so dense it almost seemed to drip with water!
Boom!
The next moment, an unparalleled heatwave erupted from the Hashira.
The surrounding air seemed to twist and shimmer from the sheer heat.
In that instant, Kyojuro Rengoku transformed. He was no longer just a man; he was the Flame Hashira.
He roared, his voice booming across the estate.
"Flame Breathing!"
"Ultimate Art!"
"Ninth Form: Purgatory!"
A long, terrifying dragon made of pure fire erupted from his blade, illuminating the growing twilight.
A flashing blade light cut through the air, so fast it was almost invisible.
With this single, devastating slash, Su Chen's pupils directly quaked.
A flood of information crashed into Su Chen's mind.
[You observed Flame Breathing, Ninth Form: Purgatory!]
[You were greatly shaken! With a sudden realization, you integrated and mastered all forms of Flame Breathing. You have instantly comprehended Flame Breathing · Ninth Form: Purgatory!]
[You are pondering...]
[You are digesting...]
[You discovered the immense power of Flame Breathing , but at the same time, you also discovered the flaws of this Breathing Style!]
[You are making improvements... You have begun to mentally deduce...]
Su Chen's train of thought suddenly paused for a moment. He was stunned.
This was the first time he had ever encountered such a situation. His ability had never reacted this way before, not just learning, but analyzing a flaw.
No! he thought, his resolve hardening. This no longer just represents me.
Kyojuro had bet his life on him. He, Su Chen, must learn this move and master it perfectly.
Suddenly.
With a mental click, everything sharpened.
[You had an epiphany!]
['Bullet Time' has upgraded. You had a sudden inspiration and comprehended a new skill – 'Bullet Domain']
[You discovered that in Bullet Domain, mental consumption is doubled! But at the same time, observation, learning, and reaction abilities are tripled, increasing to three times their original level!]
The world didn't just slow down; it seemed to freeze.
[You activated 'Bullet Domain' mode! Your observation ability became even more detailed!]
[You deduced Flame Breathing one hundred times in two seconds, and you discovered the flaws of Flame Breathing!]
[You deduced remedial measures based on the Breathing Style's flaws! You discovered a method to increase the temperature of Flame Breathing!]
[You discovered a way to improve the incorrect movements of Flame Breathing!]
[You discovered that the current Nichirin Sword is not entirely suitable for Flame Breathing. In one second, you completed improvements to the Nichirin Sword adapted for Flame Breathing!]
[You combined your ideas! Your inspiration surged! You have created the preliminary upgraded version of Flame Breathing – Blazing Flame Breathing!]
[...]
[Your comprehension has ended.]
Su Chen slowly closed his eyes.
It felt like he had been thinking for a very long time, but in reality, it was only a few tens of seconds.
Although Bullet Domain allowed Su Chen to enter an enlightened state far better than Bullet Time, its mental consumption was also terrifying.
In just those few tens of seconds, Su Chen's brain was already dizzy, and he felt mentally exhausted.
After a few seconds of rest, just standing and breathing, Su Chen slowly opened his eyes.
It was only then that he realized the true power of the Hashira's attack. He looked past Kyojuro and saw that the Flame Hashira's earlier slash had perfectly split the mountain forest beside him, leaving a long, scorched scar in the earth.