Isekai Adventure in the Dimensional Cube

This place was a very bizarre space.

The reason it was considered bizarre was because the buildings here were disorderly and presented in a very eerie arrangement.

Some were upside down, others separated from each other, some stacked like building blocks, and some even directly positioned on the walls and ceilings, making one feel as if they had entered a dream or a kaleidoscope, extremely discordant.

No one knew where this was.

Or rather, those who knew of this place were generally not human.

"Dangdang——"

At a certain moment, the sound of a pipa being played abruptly appeared, and a figure suddenly materialized here as if they had teleported.

"This place is...?"

The figure was initially taken aback, but then recognized the place.

"Infinite City?"

Infinite City, a castle unknown to man, but which truly existed in this world.

It was a major stronghold of ghosts.

It was not located on any particular spot on Earth but existed like this, within a bizarre space.

Now, someone was here, summoning the ghosts, gathering the remaining few of the Twelve Kizuki's Upper Moons.

For instance, the one who had appeared here at this moment.

Peach-red short hair, covered all over in deep blue tattoos.

Indeed, it was Akaza, who had once died.

As Akaza appeared in Infinite City, another person also approached from behind him.

"Ah, my dear Akaza, is that you?"

The newcomer moved affectionately towards Akaza, smiling as they spoke.

That was a young man with white, oak-colored hair that looked as if it had been drenched in blood, rainbow-colored irises, wearing a red shirt with a black collar.

The young man was slender but taller than Akaza, and his eyes like rainbow gems each bore the characters "Upper Moon" and "Two," revealing his identity to others.

He was Douma, the second-ranked of the Twelve Kizuki, just below the Upper Moon One—among the ghosts.

"Long time no see, have you been well lately?"

Douma reached out his hand, seemingly about to pat Akaza on the shoulder.

However, Akaza punched away the hand Douma had extended, with such force that he broke it.

"Don't touch me."

Akaza coldly stared at Douma, his expression plainly stating that if Douma dared to reach out again, he would kill him.

Such a hostile attitude, not even shown to Reiger, was now displayed by Akaza.

This made it clear how much Upper Moon Three disliked the rank above him, Upper Moon Two.

Yet, Douma seemed unfazed.

"How heartless, and here I am caring for you."

Douma shook his limp, tore-off hand like a rag, and soon it regenerated.

This ability to instantly regenerate a severed hand, if seen by a swordsman of the Demon Slayer Corps, would surely amaze them.

"You seem to be doing quite well; that puts me at ease," Douma said with a smile to Akaza. "I was worried that after your head had been chopped off once, even if you survived, there would be some lingering effects."

"Do you want to try it?" Akaza replied coldly: "If you want to try, I can twist your head off your neck as well."

"If that would make you happy, then I'm happy to oblige," Douma's smile never faded as he said, "Shall I twist it off myself? You can take it home if you like!"

Though Douma seemed to be joking, Akaza knew that if he agreed, this person would truly not mind twisting off his own head.

"Tsch..."

Akaza emitted a sound of irritation, emanating an air of ferocity.

Just as Akaza was about to attack Douma, a deep voice sounded.

"Enough..."

The somber voice boomed like distant thunder in the ears of both Akaza and Douma, causing them to simultaneously turn their heads to look to the side.

There, without anyone noticing when, another person had appeared.

The person was dressed in a purple serpent patterned kimono and black riding hakama, hair tied into a high ponytail, with red demon patterns on the left forehead and right chin down to the neck, and a katana strapped to his waist, looking like an ancient samurai.

This ancient samurai had exactly six eyes, three pairs, with the middle pair inscribed with characters.

Left eye — "Upper Moon."

Right eye — "One."

The mightiest of the Twelve Kizuki, just under the Demon King Kibutsuji Muzan—the Upper Moon One, made his appearance.

"Kokushibou..."

Akaza looked at the other with eyes filled with hostility, battling spirit, and seriousness.

"Lord Kokushibou! It's been a long time!"

Douma still had the same warm, affectionate demeanor, seemingly joyful upon seeing the strongest of the Twelve Kizuki, the only Upper Moon ranked above him.

Kokushibou ignored Douma's greeting, only staring intensely at the two with all six terrifying eyes.

"This is a direct summons from Lord Muzan... Foolishness here... Continue the foolishness... I will intervene..."

Accompanied by such words, a pressure strong enough to overwhelm everything around immediately emanated from Kokushibou.

Feeling this pressure, Akaza's expression grew increasingly serious, and even Douma stopped smiling playfully.

The three of them then looked ahead together, gazing at the person who had summoned them to Infinite City.

It was a woman holding a biwa, dressed in a white kimono, with long black hair, bangs so long they covered the upper half of her face, making it completely impossible to see her eyes.

Clearly, the sound of the biwa that had appeared in Infinite City was her doing.

"Lady Nakime!"

Douma greeted the biwa-wielding woman seated on the building at the other end.

"Where is Lord Muzan?"

Akaza also asked aloud.

Nakime was responsible for managing Infinite City, the city demon. Although she did not belong to the Twelve Kizuki and had no number, she was a close attendant of Kibutsuji Muzan, specifically assisting him like a secretary. Therefore, the demon members of the Twelve Kizuki did not consider her a subordinate demon of lower status.

The sudden appearance of Akaza and others in Infinite City was also due to Nakime's Blood Demon Art.

Since Nakime had summoned the Upper Rank demons using Blood Demon Art, there was no doubt that Kibutsuji Muzan had instructed her to do so.

Indeed, that was the case.

"Lord Muzan is already here,"

Nakime's ethereal voice resounded at that moment, everyone felt the space before them suddenly spiral and distort.

Immediately following, a Japanese-style door opened before all the demons, revealing a room utterly misfitting for Infinite City.

It appeared to be a study, filled with various bookshelves and books.

A tall young man, who had taken off his coat and was wearing a suit, with skin pale as paper, was engrossed in a book in front of a bookshelf.

The young man stood with his back to the demons and did not even think of turning around as he appeared before them, continuing to read intently.

But upon seeing him, all the demons immediately knelt on one knee.

"Lord Muzan,"

Kokushibou, Douma, and Akaza spoke with utmost respect.

The young man was none other than the progenitor of demons, the Demon King who had lived for a thousand years—Kibutsuji Muzan.

He seemed just like an ordinary human male, giving off no unusual aura from his back.

However, the moment he opened his mouth, the entire Infinite City seemed to tremble.

"Gyuutarou, Daki…"

Kibutsuji Muzan's voice, indifferent as if void of any emotion, said thus.

"They are dead."

This statement made Akaza, who was kneeling, tighten his pupils.

"Gyuutarou and Daki are dead?" Douma said in shock, "What happened?"

Kokushibou did not speak, merely raising his head, his six eyes also showing a hint of surprise.

It had been 113 years since there had been any personnel change among the Upper Rank, and now, suddenly, two had died?

What exactly had happened?

However, the astonishment of the demons was utterly disregarded by Kibutsuji Muzan, he did not even intend to explain the cause and effect.

"I haven't felt this angry in many years,"

Kibutsuji Muzan's icy voice, laden with towering rage, echoed in the ears of the demons.

"It's not because someone from the Upper Rank died, but because of your incompetence."

In an instant, a terrifying pressure, as if ready to grind all the present demons into minced meat, pervasively filled Infinite City.

"Because of your incompetence, the Blue Spider Lily has remained unfound, putting me in such a predicament."

"You tell me, what do I need you for?"

"You, what use are you?"

These words, each resonating heavily in the demons' viscera, shaking their bodies, caused blood to flow from the corners of their mouths, nostril tips, ears, and eyes.

The demons immediately dared not make even a sound.

This was also the first time they had seen Kibutsuji Muzan so enraged, and their hearts couldn't help but feel panicked.

Kibutsuji Muzan was a merciless person, and a cruel one too. Generally speaking, when he was this furious, it usually meant one or two people would have to die to quell his anger.

Even though they did not know what had happened or why Kibutsuji Muzan was so furious, they could only endure it.

Reason with him?

That was useless with Kibutsuji Muzan.

This Demon King was capricious—if you tried to reason with him, he would surely twist off your limbs on the spot.

Even the slightest thought in this regard was forbidden, because Kibutsuji Muzan could read their thoughts and hear their inner voices.

Thus, even though the demons were high-ranking, among the top three in the Upper Rank, they could only let Kibutsuji Muzan vent his anger on them.

After a long while, Kibutsuji Muzan slightly calmed his anger.

"I'll give you one last chance,"

Kibutsuji Muzan spoke coldly.

"Go prepare, the war is about to begin."