Muzan: The Demon Slayer Corps Is a Bunch of Lunatics!

At the same time.

In an unknown dimension, thousands or tens of thousands of miles away from Mount Fujikasane — Infinity Castle.

In the boundless void, layers upon layers of Japanese-style rooms, crisscrossing suspended corridors, upside-down staircases, and indescribable shoji doors... stretch out in the darkness.

"Zheng--"

A melodious sound from the Biwa resonated through the endless void.

Nakime sat gracefully on the tatami mat, her long hair covering her face, revealing only one large eye. Her pale fingertips slowly brushed across the strings of her koto.

In a study not far from her.

A young nobleman, dressed in a black suit with a snow-white shirt underneath and a silver pocket watch on his chest, sat quietly at his desk.

That handsome yet otherworldly face lacked any warmth befitting a living person.

Her slightly wavy black hair cascaded down her back, and every gesture she made exuded a nobility and composure that transcended a thousand years.

The ancestor of ghosts - Muzan Kibutsuji.

At this Muzan, Muzan was in a fairly good mood.

He shook a glass test tube in his hand, watching the blue chemical reagent inside refract colorful light.

Long ago, because all the Lower Rank members were weak and only knew how to ask him for his life essence, and even got wiped out by Giyu Tomioka while cosplaying as a speed bump, Muzan, in Muzan, announced on the spot that the Lower Rank positions were permanently abolished!

Only the Lower Rank Five moon is weary.

Because of Rui's distorted and morbid psychology, his obsession with building a false family bond, which Muzan resonated with Muzan's deep-seated, perverse belief in absolute domination, he was exceptionally allowed to retain his place, becoming the only surviving Lower Rank Moon among the entire Twelve Kizuki.

Muzan always regarded this obedient and sensible little spider as a pet that he found quite pleasing.

Three months ago, Muzan discovered that Rui was no longer on Mount Natagumo. After some maneuvering, he found out that Giyu Tomioka had taken him away!

They said it was some kind of trial product.

Are you kidding me?

Using his Lower Rank as a whetstone? Doesn't the Demon King have any dignity?!

But who has the ability to "break out of the Heavenly Prison"?

It's fair to say that as long as that damned Water Hashira is there, neither Akaza nor Kokushibo, nor even all the Upper Rank One, will make any difference!

As for him going himself?

Stop joking. He's just a subordinate; why are you expecting him to work his life away? Does he even know how valuable he is?

Of course, it's not that Muzan Kibutsuji was afraid of Giyu Tomioka, it's just that it's pointless!

He's not afraid of a cricket swordsman at all!

He's the Demon King! The Demon King! Do you understand?

Looking at it from another angle, being captured and taken to Mount Fujikasane had its advantages, since it meant he had infiltrated deep into enemy territory, didn't it?

However--

"Snap!!"

The glass test tube in Muzan's hand was instantly crushed to pieces by a terrifying, out-of-control force!

"Thump!!"

The link... is broken?!

The ancestral bloodline link that had lasted for half a century and was deeply rooted in the body of Lower Rank Five, Rui, was forcibly severed and annihilated!

Worn out!

"... What happened?"

Muzan's handsome and noble face instantly darkened, and a cold light flashed in his blood-red plum blossom-shaped vertical pupils.

"That good-for-nothing... shouldn't he be trapped in the Demon Slayer Corps' Mount Fujikasane test site?"

"How could a bunch of weaklings who aren't even proper swordsmen possibly kill him?"

"Could it be a Pillar-level swordsman who has made a move?!"

Muzan's eyes were icy cold.

As the progenitor of demons, he possessed the privilege of accessing the memories of all lower-ranking evil spirits before their deaths.

Without any hesitation, Muzan slowly closed his eyes!

However--

The instant those fragmented and shattered memories were projected into Muzan's mind!

This progenitor of demons, who lived for a full thousand years...

He's completely gone mad!

--

In the center of that devastated ruin stood a tall and straight young man.

A head of long, fiery red hair dancing wildly in the gale!

And... the fiery demonic runes on his forehead, burning as fiercely as the blazing sun!

Zoom in!

On either side of the boy's earlobes, two Sun Wheel Hanafuda Earrings engraved with sun patterns swayed gently in rhythm with his breathing!

That nightmarish symbol—the legacy of Yoriichi Tsugikuni —that would haunt him even after he turned to ashes and hundreds of reincarnations passed, a symbol that would always jolt him from his nightmares whenever he recalled it!!

The boy held the Red Nichirin Blade high in his hand!

The blade not only flowed with the golden-red flames of the Sun Breathing, but also rolled with a layer of blood-red Heat Haze that specifically countered the bodies of demons!

The aura emanating from that boy clearly carried the blood of Kibutsuji Muzan!

However!

That little bastard is wearing Demon Slayer Corps haori!

Shouting loudly into the camera:

"I am human! I believe in science! I believe in the Demon Slayer Corps!!"

"Boom--!"

Muzan's mind went completely blank in that instant!

My worldview is shattered!

Cognitive collapse!

Out-of-body experience!

"Ugh... Ugh!"

His previously impeccable gentlemanly facade vanished in an instant!

"Impossible... This is absolutely impossible!!"

"That little brat from the Kamado family who wears earrings... shouldn't he have been torn to pieces by that Water Hashira that hates ghosts long ago?!"

"Why is he still alive?! Why is he not only alive and kicking, but he's also brazenly wearing a Demon Slayer Corps uniform?!"

Muzan gripped his tie Muzan, ripping off all the buttons, his eyes bursting open and tears of blood streaming down his face.

"Kagaya Ubuyashiki... you blind man whose half-body is rotting in a coffin! Are you insane?! Has your entire Ubuyashiki Clan gone mad?!"

"For hundreds of years! Your Demon Slayer Corps has been using justice, purity, acting on behalf of heaven, and the separation of humans and demons as a facade!"

"So, behind the scenes... you guys actually brazenly recruited a demon as a full-fledged team member?!"

"Damn it! The Demon Slayer Corps recruits demons as swordsmen?!"

"Have you humans no shame?!"

Muzan was so angry that every cell in his body was trembling.

But that wasn't what terrified him the most.

What sent chills down his spine the most was the Red Nichirin Blade wreathed in blood-red Heat Haze from his memory!

"That flame... what the hell is that evil thing?!"

"As Blood Demon Art... it's specifically used to ignite and devour the blood within evil spirits?! Using the essence of its own kind as fuel to nourish itself?!"

"Sun Breathing... Demonic Body... and this demonic fire that devours its own kind..."

Muzan, his Adam's apple bobbing violently, cold sweat dripping from his chin onto the floor!

It's like he conjured up a lightning bolt for himself.

It was supposed to be a powerful weapon intended to counter the Demon Slayer Corps, but it's turned against us instead?!

Oh my god, what kind of plot twist is this?!

Below, hearing the loud crash of furniture shattering in the study, Nakime trembled all over, not daring to even breathe.

A long time.

The heavy, disordered breathing in the study gradually subsided.

Muzan, supporting himself on the table, shakily stood up again.

He straightened his tattered tie, and the anger and violence that had been on his pale, paper-white face vanished in that instant.

"This Demon Slayer Corps... is absolutely the most fucking perverted, most unethical, and most utterly shameless bunch of lunatics in the entire past thousand years!!"

Muzan closed his eyes.

Nakime!!

"Zheng--" Nakime quickly plucked the strings of her zither.

"From this day forward, at this very moment! All entrances and exits to Infinity Castle are sealed off!"

"Including Kokushibo and Akaza, all members are now Upper Rank and are strictly forbidden from stepping outside the Infinity Castle!"

"Anyone who dares to go out to forage without permission will be ground to dust!"

"Anyone who dares to bring those lunatics from the Demon Slayer Corps here, I'll feed them to the dogs first!!"

Muzan straightened his suit, sat on the sofa, and sneered:

"I'll focus on potion research here in Infinity Castle! Occasionally, I'll venture out to gather some funds and information!"

"They can conduct the selection process however they want, and kill as many scoundrels as they want!"

"Human lifespan is a mere hundred years! These lunatics and freaks will all eventually die of old age and illness in the long river of time, and be laid to rest..."

"The one who survives to the end is still only me!!"

"Zheng--!"

Accompanied by the Biwa of Nakime's biwa.

Countless wooden doors closed shut in mid-air with a resounding crash!

The entire Infinity Castle sank into the depths of the dimension.