With the advent of firearms, the tides of the era had long since shifted. The once-dominant samurai class had gradually faded into history.
An untrained civilian, armed with nothing more than a gun, could now look down upon a warrior who had trained for years—someone with superior physical ability—and say with utter disdain:
"Sir, the times have changed."
And yet, the swordsmen of the Demon Slayer Corps—those who stood against demons—still clung to Nichirin Swords, weapons of a bygone age.
Was it stubbornness?
No.
It was necessity.
"Firearms are indeed powerful," Kiriya Ubuyashiki said with a faint, wry smile. "Against humans, they are extremely effective. But against demons… their effectiveness is very limited."
This was not a question Soma alone had pondered. Kiriya's father had once considered it as well. He had purchased firearms, stockpiled explosives—even gone so far as to bury large quantities of them beneath his own residence, preparing for the day Kibutsuji Muzan might appear, resolved to perish together with him if that moment ever came.
But in the end… it was little more than a desperate hope.
Setting aside whether such measures could even kill Muzan, his cautious nature—honed over centuries—meant he would never recklessly walk into such a trap.
And yet, if it were possible, Kiriya's father would not hesitate to offer himself as bait.
"In my residence, there are also several firearms," Kiriya continued. "Among them, the most advanced is the Mondragón automatic rifle. But even with such a weapon, the reload speed is far too slow."
He paused briefly before continuing.
"Even the weakest demons move at speeds more than three times that of a normal human. By the time a swordsman fires a single shot, the demon would likely have already closed the distance. There would be no opportunity to reload a second time."
"For humans, one bullet can decide the outcome of a battle. But for demons… wounds caused by bullets are almost negligible. Their bodies can regenerate rapidly, making such injuries meaningless. And if one were to discard the firearm and reach for a Nichirin Sword at that point—it would already be too late."
As Soma listened, the long-standing question in his mind finally began to unravel.
It wasn't that the Demon Slayer Corps clung to swords out of tradition.
It was because they had no better alternative.
Demons were fundamentally different.
While bullets possessed strong penetration, they lacked the ability to sever a demon's neck—the one decisive method of killing them. And with their formidable regenerative abilities, injuries that would be fatal to humans were little more than inconveniences to demons.
Beyond that, firearms were ill-suited for close combat.
Encounters between demon slayers and demons typically occurred at extremely close range. Given a demon's speed, aiming a firearm was already difficult—and once the distance closed, the weapon lost its advantage entirely.
In contrast, a Nichirin Sword offered far greater flexibility and adaptability in such situations.
There was also the matter of endurance.
A firearm's ammunition was limited, and reloading took time. If a demon wasn't killed quickly, it would simply regenerate and continue fighting. A Nichirin Sword, however, could be used continuously without such limitations.
And then there were practical concerns—the high cost of firearms, and government restrictions.
The Demon Slayer Corps operated as an unrecognized, secret organization. They had no legal means to acquire or deploy firearms on a large scale. Moreover, the authorities had no desire for the existence of demons to become widely known—and the noise and destruction caused by gunfire would make secrecy nearly impossible to maintain.
…
"I see," Soma murmured after hearing the explanation.
At last, it all made sense.
"But compared to that," Kiriya added with a faint, uneasy smile, "what worries my father most is the possibility of demons using firearms themselves. If demons were to wield guns… that would be a truly terrifying situation for the Demon Slayer Corps."
He paused, then said quietly, "In fact… some demons have already begun attempting to use them."
"What?" Soma's eyes widened slightly in surprise.
In his memory, the only instance he could recall of firearms being used was Genya Shinazugawa—who wielded a double-barreled shotgun, blasting apart two of Hantengu's clones with just a couple of shots.
But demons using guns?
That… he had never seen.
Or perhaps—
He simply hadn't paid enough attention.
"Currently, a demon suspected of using firearms has appeared in Tokyo. Father has already dispatched Kyojuro Rengoku to handle it."
Kiriya Ubuyashiki spoke in a low voice, concern flickering in his eyes.
If demons began using guns against Demon Slayer swordsmen, it would be an entirely different matter from humans using guns against demons.
"A demon using firearms… and Kyojuro is the one sent to deal with it?" Soma took another sip of his drink, his thoughts turning inward as he searched his memory.
And then, faintly, it came back to him.
There had been such a demon.
If he remembered correctly, it was one of the Twelve Kizuki—the Lower Rank Two, Hairo.
A man who, in life, had revered the way of the sword, only to be defeated by soldiers wielding firearms—mocked for his devotion to bushido. After becoming a demon, he had come to believe that no matter how refined one's swordsmanship might be, it could never surpass the power of a gun.
Perhaps he was the first demon to truly embrace firearms.
And yet, such a demon—wielding a weapon that was largely ineffective against other demons—had still risen to the rank of Lower Two.
If there wasn't some degree of special favor from Kibutsuji Muzan involved, Soma found that hard to believe. Perhaps Muzan, too, had begun to recognize the potential of firearms… though for now, it was likely still in the experimental stage.
…
"Compared to us using firearms, what concerns us more is demons doing the same," Kiriya continued quietly, his tone heavy with unease. "If possible, Father would avoid deploying firearms on a large scale. It could easily lead to demons imitating us."
The world had already begun to change.
With the spread of guns, everything was shifting.
And yet, that cautious demon—Muzan—might not have fully taken notice of it yet. Compared to humans, demons already held overwhelming advantages. Perhaps it was arrogance, or perhaps something else, that made him dismiss such developments.
Much like the samurai of the past—
Confident in their strength, charging forward with blades in hand, believing they would triumph as they always had—
Only to be cut down like wheat by untrained men armed with guns.
And only then realizing…
That the world had changed.
Even so, many still clung to the illusions of that old era, unwilling to wake from the dream.
For the Demon Slayer Corps, there was a quiet hope—that Kibutsuji Muzan would discover the true potential of firearms as late as possible.
Even a little delay would be enough.
And so, they continued—almost stubbornly—to rely on the swords of a bygone age.
…
This brief exchange only deepened Kiriya's admiration for Soma.
Firearms were not something ordinary swordsmen thought deeply about, yet Soma clearly understood the implications far better than most.
Such foresight was rare.
Many people had yet to grasp even the most obvious changes brought by this new era. In remote regions, some samurai still clung stubbornly to their outdated pride, unaware of how the world had already moved on.
…
In a courtyard wrapped in blooming wisteria,
the Master of the Ubuyashiki family, Kagaya Ubuyashiki, performed another divination.
But the future… had grown even more obscure.
In his earlier readings, there had once been a clear sign—that within the coming years, Kibutsuji Muzan would intrude upon the Ubuyashiki Mansion. For that very possibility, he had long since buried enough explosives beneath the grounds to destroy the entire area, steeling himself to act as bait and drag Muzan down with him.
And yet now, the future had blurred once more, becoming increasingly unpredictable.
"Cough… cough…"
A violent fit of coughing seized him. He raised a hand to his mouth, but the coughing wouldn't stop. When he finally lowered his hand, his palm was stained with bright, vivid blood.
He tried to rise, but his legs refused to support him. Again and again he struggled—yet each attempt ended in failure.
Rapid footsteps approached.
Two young girls in pink kimonos, their faces youthful and nearly identical to Hinaki's, their hair just as white, hurried to his side and helped him up.
Once seated, Kagaya Ubuyashiki took a shallow breath before speaking.
"The wheelchair I requested a few days ago… is it ready?"
Ubuyashiki Nichika and Ubuyashiki Kanata both stiffened, their gazes instinctively falling to their father's legs. They understood all too well what such a request meant.
"It was bound to happen eventually," Kagaya said softly. "It's simply… come a little sooner than expected."
Sensing the worry in his daughters' eyes, Kagaya Ubuyashiki simply shook his head, unconcerned. Then he lifted his gaze, looking out through the window at the wisteria blooming in full splendor.
"Compared to the swordsmen who are devoured by demons… compared to those who risk their lives fighting them… they are the ones who truly deserve our concern."
"But Father, you are just as important," one of his daughters protested softly. "Without you—without the Ubuyashiki family—how could so many powerful swordsmen unite as one?"
"And without you, how could they fight without fear or hesitation? Everything they have… it's because of you. Because of the Ubuyashiki name."
Ubuyashiki Nichika puffed her cheeks slightly, unable to hide her dissatisfaction. "Father, you need to take care of yourself too. We cannot lose you."
"I know," Kagaya replied gently.
With their help, and after Ubuyashiki Kanata had pushed over the wheelchair, he allowed himself to be seated. Slowly, they wheeled him before a mirror.
There, he saw himself clearly.
Not only had his legs grown completely weak, but the purple markings on his face had spread even further.
The curse… had deepened.
He raised a hand, lightly tracing the darkened veins creeping across his skin. A shadow passed over his expression. Though the Ubuyashiki family had mitigated some of the curse's effects through generations of union with priestly bloodlines, it still remained deeply rooted.
As long as Kibutsuji Muzan existed, the curse would never disappear.
What he was enduring now… his son, Kiriya, would one day have to endure as well.
For generations, no male member of the Ubuyashiki family had lived past the age of thirty.
"Whatever happens, I hope this tragedy ends with my generation."
He clenched his teeth, yet beneath that resolve lay a profound sense of helplessness. If there were even the slightest chance, he would willingly stake his life to destroy Kibutsuji Muzan.
But Muzan was far too cautious.
He would never allow such an opportunity to exist.
At least in this generation, things were slightly better—Muzan had finally begun to leave traces behind. In the past, there had been nothing. Not even a shadow to follow.
"Relying on your near-immortality… do you believe that, given enough time, these swordsmen will simply age, weaken, and die? That eventually, none of them will pose a threat to you?"
"Just as you once did when facing Yoriichi Tsugikuni—choosing not to confront him directly, but simply waiting… waiting for him to grow old, for his strength to fade, until he could no longer wield his blade. And only then sending Kokushibo to claim his life with ease?"
Supported by Nichika and Kanata, Kagaya was wheeled into the courtyard. He gazed quietly at the blooming wisteria.
"But all these years… centuries have passed, and you have never changed. You remain arrogant—always underestimating us, underestimating the Ubuyashiki family, underestimating those who were once your own kind."
A breeze stirred, carrying a single wisteria petal into the air before it drifted down into his outstretched hand.
Hundreds… thousands of years.
One powerful swordsman after another had been worn down by time, their lives ending one by one.
And yet—
The Ubuyashiki family still endured.
The Demon Slayer Corps still endured.
"Perhaps it won't be long before I die. And my son, Kiriya, will follow after me. But the Ubuyashiki family will remain. The Demon Slayer Corps will remain. As long as new blood continues to flow in, the Corps will never disappear."
"And we… will continue to lead them, walking the path of hunting you."
He looked down at the wisteria petal resting in his palm, his thoughts drifting to the recent Final Selection overseen by Kiriya.
"The selection at Mount Fujikasane has concluded, hasn't it? How did it go? How many passed?"
Aside from the previous year, which had been something of an exception, each selection usually produced only a handful of successful candidates. And beyond Mount Fujikasane, similar trials were held elsewhere as well.
"Yes, Father," came the reply. "Kiriya has sent word—this time, a total of one hundred and sixty-four candidates passed."
"What…?"
Kagaya Ubuyashiki, who had been leaning back in his wheelchair, abruptly straightened, shock flashing across his eyes. Aside from the previous year—when an anomaly like Sabito had led to an unusually high number of survivors, more than sixty—the number of successful candidates in past selections had rarely exceeded seven or eight. Most years, only three or four made it through.
But one hundred and sixty-four…
The number was almost beyond comprehension.
Unless, like that previous year, the quality was uneven, then for the Demon Slayer Corps, such an influx of fresh blood would be nothing short of a powerful boost.
"…Haa."
After a long moment, Kagaya finally steadied his breathing and asked, "Could it be that someone like Sabito appeared again?"
If a swordsman of that caliber had truly emerged, they could not afford to lose such talent again.
"That's not the case, Father," Nichika replied gently. "According to Kiriya, although the candidates suffered heavy losses on the first day, from the second day onward they began to cooperate… forming groups of their own accord."
As he listened, Kagaya fell silent for a long time, unable to respond immediately.
Team coordination and structured group training were things usually introduced only after the Final Selection, when survivors would be assigned into squads. Yet these candidates… had already begun to act with that awareness during the trial itself.
"Kiriya said… all of this was influenced by someone named Soma."
Kagaya lowered his gaze, looking at the wisteria petal resting in his palm. "I recall that Mr. Urokodaki mentioned the inheritance of the Sun Breathing style before… and this Soma was part of that discussion as well."
"Yes, Father. And Kiriya holds him in extremely high regard—he even admires him," Nichika added softly. "He personally negotiated with the Swordsmith Village… just to have multiple weapons forged for him."
Kagaya lifted his head, his eyes resting on the blooming wisteria tree in the courtyard.
"Kiriya, who has always followed the rules so carefully… has finally taken a step of his own."
As both a father and someone who had once been young himself, Kagaya understood this feeling all too well. Back then, when he first met Gyomei Himejima, he had felt the same certainty.
Even though Gyomei had been accused of crimes severe enough to warrant execution—crimes that required tremendous effort and influence to overturn—Kagaya had still chosen to save him, to have him released from prison.
From the very first moment he saw him, he had known.
Gyomei Himejima would one day become a pillar of the Demon Slayer Corps.
And now… was Kiriya experiencing that same conviction?
Back then, his own father—when he was still young—had likely felt something similar as well. Perhaps when he met Rengoku's father…
Generation after generation, the legacy continued.
Even if he were to die, even if Gyomei were to fall, Kiriya would grow. And one day, Kiriya's son would take up the mantle in turn. The cycle would continue, unbroken.
Kibutsuji Muzan believed that time would erode them—that the passing years would wear down their will, their resolve, until nothing remained.
But in the end…
He had underestimated them far too much.
And above all—
He was far too arrogant.