"Then I'll be blunt—I don't have some demon-eater constitution. I'm the true primordial demon. I've been alive since the Sengoku period."
After a brief silence, Sanemi Shinazugawa was the first to respond. The look in his eyes was the same one he'd give a lunatic who had wandered out of an asylum.
"Has your delusion gotten so bad that you'd interrupt what the Master was about to say just to spout nonsense?"
"No, I'm serious. I only made that story up back then because I was in a bad mood. I never expected something like that to actually exist." Hiru let out a long breath and glanced at him. "If we're being honest, your brother's the real demon-eater."
"I observed him during the evaluation. Demon-eaters can gain a demon's power by consuming its flesh and blood, and they're able to reattach severed limbs. But they can't regenerate, nor can they freely change the size of their bodies. The strength they gain after becoming part demon depends entirely on how powerful the demon they consumed was."
Sabito let out a sigh.
"Hiru, if you're saying this just because I teased you before about always turning into a child with that demon-eater constitution, then I apologize. But no matter how much we joke around, we shouldn't make light of something the Master was about to announce."
But this time, facing the group's expressions—some helpless, others reproachful—Hiru didn't brush the matter aside like usual.
Instead, he turned to Kyojuro with a look even more exasperated than theirs.
"Hey, Kyojuro, do you get how I feel now? No one believes me. I don't even know why everyone trusts me this much!"
Kyojuro nodded slightly.
"Indeed… when you put it that way, Hiru-dono truly has had a difficult time all these years!"
Hearing that response, the Hashira finally realized something was wrong.
They exchanged glances, yet no one spoke.
Or rather, none of them knew how to begin.
What were they supposed to ask?
Ask why he had become a demon?
Judging by how Hiru usually treated demons, even a fool could tell there had to be some hidden reason.
Ask why he had concealed his identity to join the Demon Slayer Corps?
But the truth was, he had never really concealed it at all. They simply hadn't believed him.
…
So now, none of them knew how to bring it up.
Seeing their hesitation, he could only sigh and raise both hands.
"Anyway, I'll prove it to you. Just try not to be too startled."
"Blood Demon Art: Painting the World Scroll — Memory Scroll."
An invisible ripple spread outward.
Uzui clearly saw several of the Hashira suddenly lower their heads and collapse unconscious. His brow furrowed.
Before he could ask what was happening, a far stronger wave washed over him.
Even he couldn't resist the sudden drowsiness.
His eyes closed.
...
[Wake up. A shinobi must remain alert at all times.]
"Head of the house… Lord Head of the House…"
[Head of the house? Didn't I pass that position to my younger brother? Is that Hiru guy really a demon? What does this Blood Demon Art do—make people relive the past? Is this some kind of illusion?]
Uzui opened his eyes impatiently.
But the moment he saw his surroundings, he froze.
The house before him had the same classical elegance as his own family estate, yet it was clearly somewhere he had never seen before.
[Where is this…?]
"I know you're exhausted from inheriting the position of family head, but please gather yourself quickly. Otherwise the elders will start gossiping again."
He looked toward the man speaking beside him, frowning.
"…Who are you?"
"Lord Hiru, are you joking with me?" The man sighed, helplessness practically spilling from his voice. "I'm Tomohisa. I used to serve as Lord Michikatsu's advisor, and now I serve you. We've worked together for so long—surely you haven't forgotten my name?"
[Lord Hiru?]
Despite his doubts, Uzui—trained since childhood in every discipline expected of a shinobi—quickly forced himself to calm down.
Recalling Hiru's usual expression and tone, he spoke.
"My apologies. I just woke up, so my head's still a little foggy. What's the matter?"
"Of course there's a problem. You haven't handled today's clan affairs yet. And I've told you this many times already," Tomohisa said sternly. "You're the head of the family now. Don't smile at people so casually, and your tone is far too gentle. You must carry yourself with the dignity of the family head. Fix your expression at once.
"And your current appearance is completely improper. I know the ceremonial robes are cumbersome, but you can't let Ishika and Tanaka bring you only your everyday clothes just because they don't understand proper protocol."
Under Tomohisa's relentless scolding, Uzui had no choice but to quickly change into proper attire and begin dealing with the day's affairs as instructed.
By the time he regained full awareness, the sky had already grown completely dark.
And the man named Tomohisa was still chattering beside him.
Finally, Uzui couldn't take it anymore.
"Hey, Tomohisa, how long have I been the head of the family?"
"You've been head of the family for a year and a half now. But if you're asking about when Lord Michikatsu left, that was nearly two years ago."
"With this many daily matters… that guy must've had a rough life…"
"What did you say?"
"Nothing. Tomohisa, you should go get some rest. I want to take a walk by myself."
"…Understood. But please rest early as well."
Only then did he finally get some time to himself.
After wandering around for a while, he stopped and looked around.
"Alright. I don't know what that guy's trying to do, but I should at least figure out the layout first—who's there?!"
He spun around sharply.
The moment he saw the approaching figure, his pupils shrank.
The man had the exact same face as Yoriichi.
But behind him loomed a faceless black shadow—something Uzui had never seen before.
And that aura…
[A demon? But that face… is it Yoriichi?]
"It seems you noticed. As expected—you've always been perceptive since childhood."
He tried to speak, only to discover that his body no longer obeyed him.
He heard his own voice tremble as the words left his mouth.
"…Big brother?"
[Big brother? Ah, right… Hiru did mention his older brother became a demon. Is this that moment?]
He watched as the man slowly walked closer.
"I am no longer Tsugikuni Michikatsu. I am Kokushibo now—a demon far stronger than any human."
"But… Big brother, weren't you a demon-slaying swordsman?"
This time, the man calling himself Kokushibo stopped.
He stood there in silence for a long time before slowly drawing the katana at his waist.
"…Not anymore. I came back this time to sever the ties of my life as a human. This weak clan would only hold me back and prevent me from moving forward."
A sense of danger unlike anything Uzui had ever felt washed over him.
Instinctively, he tried to leap away.
But he soon realized that after a brief moment of stiffness, his body had relaxed instead.
It even closed its eyes.
[Is this idiot insane?!]
Clearly, he wasn't the only one shocked.
Even the swordsman calling himself Kokushibo seemed confused by the reaction.
"…What are you doing?"
"Why aren't you resisting?"
"Father once said that when the time came, I must give everything for my elder brother. That is the very purpose of the third son's existence.
"You have returned as Tsugikuni Michikatsu, haven't you? I only hope that after you kill me, you will spare the innocent members of the clan."
[It's over. This guy's an idiot.]
Uzui felt a heavy sense of doom settle over him.
[Could it be that this moment triggered something in him and turned him into a demon?]
After a long silence, footsteps slowly retreated.
His vision cleared again, and he saw Kokushibo's back as the man walked away.
"From this day onward, I am no longer your brother. Pray that those people never cross my path at night. I will show no mercy."
"Big brother!"
Kokushibo stopped and turned his head slightly.
"…Do you still have something to say?"
He could feel his own throat tighten, his entire body trembling uncontrollably.
"After… after you leave today… I will no longer acknowledge you as my brother."
"…It doesn't matter."
He watched as Kokushibo walked away step by step without the slightest hesitation. If not for the shadow trailing behind him, the man might even have seemed reassuring.
[That's it? He didn't become a demon here?]
But just as the dryness in his eyes became almost unbearable, [his body] began moving again.
After passing through several corridors, he found himself returning to the room where he had awakened earlier.
He sat down at the desk.
After lifting the brush several times and hesitating, [his body] finally began to write.
Yet it seemed dissatisfied with what it had written—or perhaps it simply didn't know what to write. Several sheets of paper were wasted before a complete sentence was finally written.
[It has been a long time since we last parted, elder brother. I wonder if you might have time to return home for a visit.]
Once that sentence was finished, he discovered that he could move again.
He first pressed his palms lightly against his eye sockets to ease the dryness, then looked down at the letter containing only that single line.
"That earlier one was for big brother… so this must be meant for Yoriichi."
He picked up the letter and examined it several times before rummaging through the desk.
"There's no address on it? Isn't this supposed to be one of those setups where I get a clue here, then move on to the next place until I reach the final objective? This is confusing."
But the quiet did not last long.
Chaos soon erupted outside.
The sound of collapsing buildings and violent tremors reached him with startling clarity.
[An earthquake? First my brother becomes a demon, and now there's an earthquake? Is this guy cursed or something?]
"Hiru-sama!"
Tomohisa burst in with several guards, his face pale with panic.
"Please evacuate immediately! There's a monster—!"
Before he could finish speaking, a crimson mass of flesh-like tentacles pierced straight through his body.
Even as he died, the overly talkative advisor still urged Uzui to run.
As Tomohisa collapsed, he finally saw the horrific scene outside the door.
The once-elegant courtyard had been reduced to shattered ruins under the rampage of grotesque flesh tentacles. As buildings collapsed, cries of agony and desperate pleas for help echoed everywhere.
Instinctively, he tried to grab a weapon and fight.
But the men who had come with Tomohisa seized him from both sides and dragged him away at once.
"What are you doing?!" he shouted in shock and anger. "I'm the head of the house! At a time like this, I should be the one fighting!"
"Hiru-sama, please don't make things worse right now!" one of the guards—an honest-looking man—shouted. "I'm glad you're showing responsibility as the head of the family! But you're an adopted son and have never received martial training! Don't make things more dangerous! Miki and I will escort you out—just cooperate!"
"He's right!" the other guard shouted. "The most important thing right now is that you must not die! We'll hold them off! No matter what happens, you have to live! You are the head of the Tsugikuni family! As long as you live, we still have a reason to fight!"
He was just about to argue—
A brilliant flash of steel suddenly cut through the air.
Several guards chasing behind them were instantly beheaded.
As blood and flesh scattered everywhere, he saw a face he had parted with not long ago.
The expression on that face remained almost completely emotionless.
Yet the blade that had originally been raised toward him shifted direction the moment their eyes met, cutting down another group of guards rushing toward them.
[What is he doing? I'm clearly the easier target. Why didn't he—]
"It's Lord Michikatsu!"
"Why would Lord Michikatsu—"
The guards shouted in confusion.
Yet even in their shock, they hesitated only for a brief moment before continuing to drag him away.
By this point, Uzui's mind had fallen into complete chaos.
He simply could not understand why this demon—who had chosen to spare everyone here just moments earlier—had now begun slaughtering them.
Even if demons were fickle, this was far too extreme—
BOOM—!
A deafening crash erupted.
A monstrous flesh tentacle burst through the wall, jagged teeth lining its surface as it lunged toward them with terrifying speed.
He felt himself suddenly thrown aside.
At that same moment, the sound of flesh tearing rang out behind him.
Warm blood splashed across the ground, staining the night-drenched courtyard an even deeper crimson.
Even without looking back, he knew exactly what had happened.
He saw a sword lying beside him and reached out to grab it.
But the moment his fingers touched the hilt, an overwhelming force slammed into him.
He had no time to react.
The blow knocked the air from his lungs. The sudden lack of oxygen dulled even the pain of the impact as darkness flooded his vision.
The first thing to return was sensation.
But the excruciating pain spreading through every limb made his already blurred vision darken again.
Relying on instinct alone, he forced himself upright and leaned against a nearby surface. Struggling, he lifted his head and looked at the figure standing before him.
The man was strikingly handsome.
But the shadow looming behind him—and the grotesque flesh tentacles spreading from his back—made one thing unmistakably clear.
A demon.
And without question, an extremely powerful one.
He tried to see more clearly.
But suddenly the light before him dimmed.
Kokushibo's voice rang out again.
"Stop. He is merely a fragile human with a short lifespan. Leave him alone and he will die soon enough. Consider this the last trace of mercy I possess."
[What? What is he talking about?]
"Very well. Since you say so… after all, I am a considerate superior."
"…But only this once, Kokushibo."
Those were the final words he heard.