Isekai Adventure in the Dimensional Cube

The location of the Demon Slayer Corps Headquarters was referred to as the estate of the Ubuyashiki family by Rengoku Kyoujurou.

Because the leaders of the Demon Slayer Corps are descendants of the Ubuyashiki family, who have held the position for generations, and since the corps itself was originally formed by this family, the place where the leader resides also serves as the headquarters—the Ubuyashiki family estate.

Given that the exact location of the estate was not to be easily disclosed, Reiger was not informed of its whereabouts on his way to the Demon Slayer Corps Headquarters.

What's more, Reiger didn't even have the opportunity to see the route to the Ubuyashiki estate; he sat with Rengoku Kyoujurou in a carriage that was tightly covered and was transported all the way to the destination.

Thanks to this, when Reiger stepped out of the carriage, he had no idea where he was or what place this was.

He only knew that Rengoku Kyoujurou had brought him to a very hidden location and that they had arrived at the courtyard of a luxurious house.

Tanjirou, Zenitsu, and Inosuke had not come along and were instead arranged by Rengoku Kyoujurou to go to his house.

Only Reiger and Rengoku Kyoujurou arrived at the estate, without even a servant to guide them.

Reiger glanced around and noticed the setting was beautiful.

Underfoot were stone-paved grounds.

Surrounding him were carefully cultivated plants and a stream flowing under a small bridge.

The style of the estate was traditional Japanese, exuding an air of historic weight and ancient times.

"Hmm! We're here!" Reiger, led to this place by Rengoku Kyoujurou, gave Reiger's shoulder a pat before turning towards the estate and loudly reporting.

"Flame Pillar Rengoku Kyoujurou! Accompanied by Tsukiguni Yoriichi Swordsman is here!"

Rengoku Kyoujurou's already loud voice, amplified by his deliberate shouting, echoed throughout the estate, lingering on and on.

Reiger quietly watched the scene, feeling a movement in his heart, and he looked up.

"Whoosh!" "Whoosh!" "Whoosh!" "Whoosh!"...

In that moment, a series of whooshing noises erupted, and one after another, figures rushed in from all sides of the courtyard.

They successively landed on the surrounding walls of the courtyard, looking down at Reiger standing in the center, each emanating a unique yet equally formidable presence.

"Hmm?" Seeing this, a surprised Rengoku Kyoujurou exclaimed, "Oh! You've all made it here too?"

No wonder Rengoku Kyoujurou was astonished.

As the intentionally concealed headquarters of the Demon Slayer Corps, the Ubuyashiki estate was seldom visited, even by the trusted Pillars, who rarely gathered together except for the biannual Pillar meetings where they would assemble to discuss the corps's discipline and future action plans.

Normally, the Pillars had busy schedules, responsible for overseeing vast territories and collecting information related to demons, training to improve their own strength, and dealing with various other tasks. Under normal circumstances, they wouldn't all be gathered at the headquarters.

Strangely, the biannual Pillar meeting had just recently concluded and, ordinarily, the Pillars should be out on missions or dealing with the Demon Slayer Corps' pressing duties.

Yet, at this very moment, the Pillars, rarely seen together, had once again converged.

"You've finally returned, Mr. Rengoku."

The speaker was a rather petite girl standing closest to the estate wall.

With bangs curling at the ends into a purple hue and purple pupils, she wore a mint-colored butterfly accessory in her hair, donned in the Demon Slayer Corps uniform with a haori adorned with a butterfly wing pattern, making her look like a butterfly that could take flight at any moment—extraordinarily beautiful.

She was the Insect Pillar, Kochou Shinobu.

"Yo, Rengoku, I heard you caused quite the stir on the Infinite Train, pretty cool, eh!"

Speaking was a young man with a Ninja-like posture, arms folded, standing stiffly on a tree branch.

The youth was robust, wearing a sleeveless uniform of the Demon Slayer Corps, a diamond-studded headband with light blue chain-links on either side, his silvery-white hair tied into a prominent ponytail, and he carried a sword on his back, with an extremely strong presence.

He was the Sound Pillar, Uzui Tengen.

"S-sorry, Mr. Rengoku, everyone was just really curious to see what the person who defeated an Upper Rank looks like..."

This was a shy-looking girl who honestly landed in the courtyard.

She had large light green eyes, a blushing complexion, a mole under each eye, and her cherry pink hair with three green-tipped braids draped over her body. She also wore a snow-white haori and what seemed to be a specially modified Corps uniform with a skirt on the bottom and green-striped long socks, fashionable indeed.

She was the Love Pillar, Kanroji Mitsuri.

"And then? Is that kid the one who took down an Upper Rank?"

The one speaking in such a coarse tone was a man with white spiky hair and three scars across his face, his body covered in wounds, looking quite fierce and intimidating.

The man opposite was draped in a white feathered robe emblazoned with the character "Kill," his uniform open to reveal his muscles, exuding a fierce aura that gave the sense that he could draw his sword and charge forward to slash someone at any moment, instilling a terror of being cut down.

He was the Wind Pillar, Shinazugawa Sanemi.

"... To think a brat like this could kill an Upper Moon? Hard to believe."

These words came from someone in a relatively dark corner.

The person had heterochromia with a green left eye and a golden right one, the lower half of his face wrapped in bandages, his black hair curled like seaweed, and he was draped in a black-and-white striped feathered robe, with a white snake around his neck, hissing at Reiger.

He was the Serpent Pillar, Iguro Obanai.

"Ah, so young, seems to be only a bit older than Muichirou-kun, too young to have to fight to the death with an Upper Moon, such a pity, Amitabha."

This was said by a man dressed as a monk, the most physically imposing figure present.

He clasped his hands together, tears streaming down his face, a long scar on his forehead, and his eyes seemingly completely blind. Over his Demon Slayer Corps uniform, he wore a brown kasaya inscribed with "Namu Amida Butsu," coupled with a strand of Buddha beads in his hand, and to those unaware, he might indeed be mistaken for a monk.

He was the Stone Pillar, Himejima Gyoumei.

Then, two more people leaped down from the surrounding wall and silently walked into the residence without a word.

One was a calm and composed black-haired young man who didn't engage in idle chatter, wearing a feathered robe with different patterns on each side over his Demon Slayer Corps uniform, the other a boy with mint green tips on his black hair, expressionless.

The young man was the Water Pillar, Tomioka Giyuu.

The boy was the Mist Pillar, Tokitou Muichirou.

"So you've all made it! Mm! This is memorable indeed!"

With the boisterous cry of the Flame Pillar, Rengoku Kyoujurou, the nine Pillars of the Demon Slayer Corps were now rarerly gathered together outside of their official meetings.

Reiger's gaze swept over each of them, recognizing their identities.

The Pillars were also paying attention to Reiger, to this Swordsman who was said to have slain an Upper Moon, some eyes filled with curiosity, others brimming with skepticism.

For example, Wind Pillar Shinazugawa Sanemi and Serpent Pillar Iguro Obanai did not hide their doubts.

"I say, Rengoku, you didn't let the Kasugai Crow send back false reports, did you?" Shinazugawa Sanemi bluntly said, "A brat like this killing an Upper Moon? I don't buy it!"

"Agreed." Iguro Obanai, playing with the white snake on his neck, darkly said, "The Upper Moons who haven't been replaced for over a century, not even we dare to say we can behead one of them, and suddenly a strange young Swordsman appears claiming he succeeded. Unfortunately, I don't believe it either."

"You must have teamed up, right?" Uzui Tengen held his forehead, posing peculiarly, "Although that's not very glamorous, it does make it easier to accept in terms of results."

"Ah, indeed." Himejima Gyoumei, hands together, tears streaming, "Even if it's by teamwork, slaying an Upper Moon is still a great achievement."

Wind Pillar, Serpent Pillar, Sound Pillar, and Stone Pillar thus expressed their opinions in turn, it seemed they were still confirming the accuracy of the information.

"Don't say things like that, maybe this Tsukiguni Yoriichi-kun is a genius like Muichirou-kun?" Love Pillar Kanroji Mitsuri spoke up for Reiger while fidgeting with her fingers, and after speaking, she sneakily glanced at Reiger, then secretly squealed in her heart, whispering, "Tsukiguni-kun is so handsome!"

"Mmm, he seems indeed very smart and talented." Insect Pillar Kochou Shinobu, who had been studying Reiger since her appearance, smiled and then turned to Tokitou Muichirou, "What do you think, Muichirou-kun?"

"... I don't care." Mist Pillar Tokitou Muichirou seemed uninterested in the topic.

The remaining Water Pillar, Tomioka Giyuu, had been silent from the beginning, standing there without a word, clearly not much of a talker.

Finally, it was Rengoku Kyoujurou who spoke.

"I have reported everything through the Kasugai Crow, every word is true, not a half-truth, and if there's any concealment, I'm willing to commit seppuku!"

This Flame Pillar even took the conversation to such a level.

Yet still, there were those who were reluctant to believe.

"Won't we know if it's true or not by trying?"

Shinazugawa Sanemi revealed a ferocious smirk and, in front of everyone, drew the sword at his waist.

"Shinazugawa! What do you think you're doing?"

Rengoku Kyoujurou's eyes widened as he yelled at Shinazugawa Sanemi.

"Quiet, I'm just trying a little, it should be fine, right?" Shinazugawa Sanemi sneered, "Besides, he isn't a member of the Demon Slayer Corps, so laying hands on him doesn't break any rules."

"Kid, dare to take a slash from me?"

As he spoke, a whirlwind rose around Shinazugawa Sanemi, disturbing the air in the courtyard.