Demon Slayers: Swordsman
Chapter 5 — Muzan's Fury
Deep within the shifting halls of the Infinity Castle, silence ruled like a suffocating weight. Wooden corridors twisted endlessly, floating platforms suspended in darkness as lantern light flickered across crimson walls.
Inside a hidden laboratory chamber, glass instruments and strange chemicals filled every shelf.
A boy no older than ten stood in the center of the room.
His crimson eyes suddenly burned with terrifying rage.
The test tube in his hand shattered with a loud crack, glass piercing into his palm as dark blood dripped onto the floor.
"Doma… died?" the boy whispered.
His voice trembled with fury.
"And by a kid who isn't even a Demon Slayer?"
Veins bulged across his pale face as his expression twisted into pure hatred.
In the next instant—
WHOOOSH!
Whips of flesh erupted from his body like living blades, tearing through the laboratory with impossible speed.
Glass shattered. Tables exploded. Shelves collapsed.
The entire room was reduced to rubble in the blink of an eye.
"Disgrace," the boy growled coldly.
"To die by the hands of a human."
His crimson eyes glowed violently.
"NAKIME!"
The air rippled like water.
A woman in a kimono appeared kneeling nearby, as if reality itself had folded to allow her arrival.
Her face was hidden behind long black hair as she held an old biwa instrument across her lap.
Nakime bowed deeply.
"You called, Lord Muzan."
Muzan's killing aura filled the chamber like a violent storm.
"Call all the Moons," he ordered coldly.
"How dare they die by the hands of humans?"
Nakime gently plucked the strings of her biwa.
TWANG.
The sound echoed across the Infinity Castle like a command to reality itself.
In the next moment—
Eleven demons suddenly appeared inside the chamber.
Lower Moons.
Upper Moons.
All summoned at once.
The instant they arrived—
The crushing pressure in the room forced the Lower Moons to their knees.
Their bodies trembled violently.
Blood slowly began leaking from their noses and mouths.
Even the Upper Moons bowed respectfully.
Only one remained seated.
Kokushibo.
The Upper Moon One sat calmly with his six eyes watching everything in silence.
Even he looked slightly confused.
Why was their lord this angry?
Muzan stood above them like an executioner.
His crimson eyes scanned every demon in the room.
Then he spoke.
"Doma is dead."
The entire room froze.
For a moment no one even breathed.
Then the pressure suddenly increased.
Lower Moon demons began bleeding from their eyes, ears, noses, and mouths.
Their bodies trembled violently.
The words echoed through the chamber like a death sentence.
"Care to explain why you exist?" Muzan asked coldly.
More veins appeared across his face.
"Why should I keep you around if you are just going to get yourselves killed?"
The Lower Moons immediately began begging.
"Please forgive us Lord Muzan!"
"We will become stronger!"
"We will hunt more humans!"
But Muzan's patience had already run out.
His flesh whips exploded outward like violent serpents.
SHRRAK!
In an instant—
Lower Moon Two.
Lower Moon Three.
Lower Moon Four.
Lower Moon Six.
All of them were sliced apart like paper.
Their bodies collapsed onto the floor in pieces.
Only two demon remained alive.
Lower Moon One and Five.
The survivor trembled violently, his entire body shaking in terror.
Blood dripped down their faces as thay bowed desperately.
Muzan didn't even look at them.
Instead, his gaze slowly turned toward the Upper Moons.
"Lower Moons have been dying all the time," Muzan said quietly.
"But for the first time in decades… an Upper Moon has died."
His crimson eyes burned with terrifying hatred.
"And not by a Demon Slayer."
"By an unknown swordsman."
"Without putting up any fight."
The room fell into heavy silence.
Even the Upper Moons were shocked.
Muzan's voice became colder.
"So tell me."
"Why should I keep you around?"
No one answered.
Even demons who had lived for centuries were stunned.
Finally—
Kokushibo spoke.
"A swordsman strong enough to kill Doma without him being able to fight back?" he murmured slowly.
His six eyes gleamed with interest.
"How fascinating."
Muzan immediately turned his glare toward him.
Because he understood what Kokushibo was implying.
And that thought terrified him.
That fear quickly turned into violent anger.
"No," Muzan said sharply.
"There can never be another monster like that man."
His voice trembled slightly.
"A monster like him cannot be born again."
His eyes burned with madness.
"I want him dead."
Muzan's killing intent filled the entire Infinity Castle.
"If you cannot kill him…"
His gaze slowly swept across every Upper Moon.
"I will kill you."
The Upper Moons reacted differently.
Akaza slowly grinned.
"A strong human swordsman?" he said excitedly.
His golden eyes sparkled with battle hunger.
"I want to fight him."
His smile widened.
"If he killed Doma that easily… he must be incredible."
Beside him—
Gyokko nervously licked his lips.
"A human capable of killing Upper Moon Two…"
"How grotesquely beautiful."
"I must see this creature."
Hantengu trembled violently.
"H-h-he killed Doma?!"
"Th-that's terrifying!"
"We're all going to die!"
He immediately hid behind the other demons in panic.
Meanwhile—
Daki looked shocked.
"Doma… died?" she whispered.
"How is that even possible?"
Beside her, Gyutaro scratched his neck with a twisted grin.
"A human strong enough to kill Upper Moon Two," he muttered.
"Heh… that sounds fun."
But Kokushibo remained calm.
His six eyes slowly closed.
"A swordsman powerful enough to kill Doma instantly…"
He opened his eyes again.
"I wish to meet him."
The room fell silent again.
Muzan's expression darkened further.
"Enough."
His voice echoed across the castle like thunder.
"I don't care who kills him."
"I don't care how long it takes."
"But bring me his head."
Muzan's red eyes glowed with violent hatred.
"Because if that monster truly exists…"
His voice dropped into a whisper filled with dread.
"Then he must die."
Somewhere far away—
In a quiet forest—
Ren walked casually through the trees with Kocho Sisters.
Completely unaware that the King of Demons himself had just declared his death.