"You are going to die, Shinjuro Rengoku."
Hairo stared at the man before him. The humiliation he had once suffered at this man's hands would finally come to a definitive end today.
"Father…"
Hearing the demon mention his father's name, Kyojuro Rengoku gritted his teeth. He had longed so desperately for his father's recognition, yet in the end, the chance never came. He had not even been able to return in time for his father's burial.
"Born within the flames… burning for one's convictions."
Kyojuro murmured the words softly. It was the creed passed down through generations of the Rengoku family, carved deeply into the hearts of every one of its members.
Gripping his Nichirin Sword tightly, Kyojuro fixed Hairo with his blazing eyes.
"Death is nothing to fear. That is the resolve a Hashira must carry. If it means killing a member of the Twelve Kizuki like you, every Hashira would fight with everything they have. Every Hashira would face death without hesitation."
At that moment, Kyojuro's presence reached its peak.
The overwhelming spirit radiating from him made Hairo momentarily dazed. The face before him looked almost identical to Shinjuro's, yet the feeling they gave off was completely different.
The Shinjuro he once knew had been like a setting sun, fading and collapsing into darkness.
But the man standing before him now was like the rising sun at dawn.
"And one more thing," Kyojuro said as he blocked another incoming strike from Hairo, "I am not Shinjuro Rengoku. I am Kyojuro Rengoku. Shinjuro was my father."
Only then did Hairo notice the youthfulness still lingering on Kyojuro's face.
"So you're Shinjuro's son… no wonder. The difference between you two is enormous."
Hairo still remembered the Shinjuro he had met back when he was only an ordinary demon: broken, drowning himself in alcohol, consumed by despair.
But Kyojuro was entirely different. He burned with fierce conviction and passion, like living fire itself.
"Whether it's Shinjuro or his son Kyojuro, both of you will die by my hands today."
As Hairo spoke, shadows poured out from beneath his feet like a rising tide, spreading across the ground around them. The darkness gathered around his katana grew thicker and thicker until it resembled a solidified abyss.
"Death means nothing."
Kyojuro tightened his grip on his sword and slowly raised his eyes. The fire within them remained as bright as ever.
At that moment, he seemed to see his gentle mother once more.
He wanted so badly to ask her something.
Mother, did Kyojuro do well?
The things he was meant to do.
The duties he was meant to fulfill.
Had he done them properly?
But before him, there was no trace of his mother's warm smile.
There was only Hairo, Lower Rank Three of the Twelve Kizuki.
The tearing pain in his lungs grew worse with every breath. Broken bones in his shoulder ground painfully against each other. Blood continued to pour from the wound piercing his leg, while the bullet wound at his waist burned like fire.
Kyojuro did not know whether what he had done was enough.
He only knew that he had been born stronger than most people, blessed from the very beginning with gifts others did not possess. Because of that, he believed even more strongly that he had to use his strength to do what was right.
Protect the weak.
Slay the demons who preyed upon humanity.
That was the duty he had always sworn to uphold.
And even more than that—
It was the duty of the Flame Hashira.
His body was growing weaker and weaker, yet the flames in Kyojuro's eyes only burned hotter.
He stepped back once more, narrowly avoiding Hairo's slashing blade, and tightened his grip on the hilt. At that moment, the Nichirin Sword in his hands seemed to grow hotter and hotter, the temperature rising rapidly as though the sword itself had caught fire.
Seeing this, Hairo frowned with visible disgust. The blade was beginning to radiate more and more of that hateful power of sunlight.
"Your shadows can swallow blades. They can devour every attack aimed at you, but…"
Kyojuro's gaze blazed brighter than ever as the Nichirin Sword in his hand seemed to ignite.
"Can they devour sunlight?"
"Then let me see whether you can swallow the sun itself."
Hairo's pupils suddenly contracted.
At that instant, he could clearly sense it.
It was not only Kyojuro's Nichirin Sword that radiated scorching energy now.
Kyojuro himself was burning with that same blazing power, as though something inside his body had ignited like a living flame.
The energy radiating from him made Hairo feel as though even his shadows were trembling slightly.
"Boom—"
At that moment, Kyojuro Rengoku moved again.
He was faster than before, and the blade in his hands had become even sharper and more dangerous.
Fear suddenly rose within Hairo's heart.
Earlier, whenever Kyojuro's Nichirin Sword struck him, the damage had almost entirely been absorbed by the shadows covering his body. But now, Hairo could feel those shadows gradually fading away.
His Blood Demon Art, Capture Cavity: Warwolf of Horror, was slowly falling apart.
"That's impossible…"
Hairo gritted his teeth and forced even more shadows to compress around his body.
Darkness surged toward him from every direction, desperately trying to fill the portions that had been melted away. Yet no matter how much he replenished them, the shadows continued dissolving at an irreversible pace.
Then Kyojuro swung his blade once more.
The dark crimson glow spreading across the sword grew brighter and brighter, forcing back the surrounding darkness inch by inch. To Hairo, it felt as though he were watching the sun itself rise upon the earth.
And to him, that light was fatal.
Before that radiance, his shadows had no power to resist.
They were not cut apart.
They were not shattered.
They were burned away completely.
Like withered leaves falling into a fire. Like snow melting beneath the warmth of spring. The darkness wrapped around his body let out a silent scream beneath the light before vanishing without a trace.
"T-This… this can't be possible…"
Hairo's voice trembled as he tightened his grip on the katana in his hand.
It was the only thing on his body untouched by the burning light, because it was not made of shadows. It was a real sword—the blade he had once wielded as a human, the sword that carried his former pride and dreams.
"Why has your blade suddenly changed? Why… before, it couldn't cut through…"
"This is… the Bright Red Nichirin Sword."
Kyojuro spoke softly.
It was a demon-slaying technique once lost to the Demon Slayer Corps' history, far more powerful than anyone imagined. The scorching heat it carried was far stronger, its penetrating power far greater, and the damage it inflicted upon demons far deadlier.
But compared to the Bright Red Nichirin Sword, Kyojuro realized that, in this moment, he had also gained a deeper understanding of Flame Breathing itself.
The burning passion within his heart—the passion he had suppressed after his father's death—had finally ignited completely.
He tightened his grip on the sword once again.
Kyojuro looked toward Hairo, and flames seemed to burn within his bright eyes. That blazing spirit was reflected directly through the Nichirin Sword in his hands.
At that moment, the blade truly seemed capable of drawing upon the power of the sun itself.
The pitch-black night appeared to scatter away, and the earth itself seemed to transform into a blazing sun.
"Flame Breathing… Esoteric Art."
Kyojuro swung his blade again, speaking in a low voice.
Yet those words rang clearly within Hairo's ears, like the tolling of a temple bell, like thunder rumbling across a summer sky.
"Flame Breathing… Esoteric Art… Ninth Form: Rengoku."
The blade descended.
In Hairo's eyes, it no longer looked like a sword.
It looked like—
A falling sun.
Dark crimson light exploded from the blade, transforming into a scorching burning sun.
The shadows covering Hairo's body ignited like paper tossed into flames. Starting from the edges, they burned away piece by piece, curling and crumbling into ash.
The shadow armor formed by Warwolf of Horror cracked apart beneath the light. Golden-red radiance shone through the fractures, as though another sun were rising from within his body itself.
The form of the shadow wolf collapsed.
Its wolf head.
Its fur.
Its claws.
Every shadow dissolved beneath the blazing light, revealing Hairo's original appearance once more.
The madness on his face was gone.
The mocking sneer was gone as well.
What remained was a strange calmness.
Hairo raised the katana in his hands for one final block.
Blade met blade.
There was no deafening crash of metal.
No burst of sparks.
Kyojuro's Nichirin Sword sliced straight through Hairo's katana.
The sword had been abandoned for many years, left uncared for and unmaintained. In the end, it could no longer retain the strength it once possessed.
Just like its owner had once abandoned it—
Now, it abandoned its owner as well.
Kyojuro's blade fell upon Hairo's neck.
This time, there were no shadows left to protect him.
This time, the Nichirin Sword cut directly through flesh and bone.
Hairo's head flew into the air, tracing an arc beneath the moonlight.
His body began to crumble apart as ash-gray fragments drifted from the severed neck, slowly scattering into the night wind.