The Next Day.
At Demon Slayer Hideout.
A large group of Demon Slayers stands outside the Ubuyashiki mansion, their heads bowed low in guilt and shame.
Their voices tremble, one after another.
"Oyakata-Sama… forgive us."
"But we cannot stay here anymore…"
"They've found us. We'll die if we don't leave."
"It's the only way to survive…"
Oyakata-Sama remains calm, seated gracefully as ever. He offers them a faint smile.
"I understand," he says gently. "If this is your decision… I will not stop you. You have served with honor. I am grateful… for every breath you've spent fighting beside us."
Suddenly—
A gust of wind sweeps the courtyard.
"Wait!"
All heads snap toward the voice.
Ai Hanako stands tall on the steps, her haori fluttering in the breeze. Her presence cuts through the air like a blade. Her purple eyes burn with resolve.
The slayers freeze. "Hanako-San…?"
Her gaze hardens.
"You all talk about danger, about fear… But I want to ask you—why are you really leaving the Corps?"
Silence falls.
One man hesitantly steps forward. "Hanako-San… we have no choice. The Upper Moons… they're watching us. We're being hunted."
Hanako's expression darkens. "That's it?" She steps forward slowly, her voice sharpening. "Tanaka-San… Do you remember what you said the day you joined the Corps?"
He flinches. "I—"
"You said," she interrupts, "you'd fight to protect the innocents. That you'd devote your blade to our cause... even if it cost your life."
He swallows, shame overtaking his face. "Y-Yes…"
She exhales, then raises her head slowly.
"Then answer me this."
Her voice drops, quiet but thunderous.
"If the demons have really found us…
If they're as powerful as you fear…
Why haven't they killed us yet?"
A chill runs down their spines.
No one answers.
Ai Hanako slowly stepped forward, her gaze fixed on the slayers before her.
"They haven't attacked us yet," she said coldly, "because even they aren't ready."
Her voice sharpened. "If they fight us now, it won't be easy for them either. They know there's a chance—however small—that they might lose."
Murmurs rippled through the crowd.
Then someone finally dared to speak.
"But… what about Michikatsu? The one with six eyes… Can we even touch him?"
Ai's body tensed. For a moment, words welled up in her throat—only to die in silence. She couldn't lie.
But then, a calm, worn voice cut through the stillness.
"Indeed," Oyakata-Sama stepped forward, his steps deliberate, though frail.
"We may not be able to defeat him. But that doesn't mean we are already defeated."
The crowd turned to him, eyes wide.
"In the long history of the Demon Slayer Corps… there lived one man. One slayer whose light once forced the very King of Demons to retreat. His name was… Yoriichi Tsugikuni."
"That was centuries ago!" one of the slayers cried out. "Right now… we have no one like that. Not a single person can face that monster!"
Ai smiled, "Perhaps."
She said quietly, "there is someone. Someone whose name even Michikatsu fears. Someone whose existence sends shivers down the spines of Upper Moons."
Her words gripped the slayers like a hook.
They turned to her, eyes wide.
"…Are you talking about Ren Hajime?"
"The urban legend?" another whispered.
Oyakata-Sama nodded with a mysterious smile. "That's right."
"But… does he even exist? We've never seen him. There are only rumors—stories of a child…"
Ai's voice rang with certainty now. "I've seen him. With my own eyes."
A stunned silence fell over the courtyard.
"Everything they say about him is true," she continued. "He reached Hashira level when he was just six years old—in one single night. He mastered the Sun Breathing… defeated Kizuki demons alone. And vanished like a ghost."
She looked at them all, her eyes burning.
"Demons fear his name. They whisper it in the dark. Even the strongest among them tread carefully… hoping never to cross his path."
The crowd was breathless.
"Maybe he's still alive," Ai said softly. "Maybe he's even among us, watching… waiting. But one thing is clear… he's real."
"…So it's not a myth?" someone murmured. "Ren Hajime… is real?"
Ai nodded. "And he's not the only one. We have more.
Fuji-San, our Stone Hashira. The strongest of this era.
Agatsuma-Sama. Legend says he's the only survivor of the Great War against Muzan.
And more than that… We have all of you. Each one of you standing here. You're not weak. You chose this path not out of safety, but sacrifice."
A long silence.
Then, slowly, one by one—
The Demon Slayers dropped to their knees before Oyakata-Sama, bowing low.
"Forgive us, Oyakata-Sama. We had lost hope… but not anymore.
We will fight, even if it's our last breath.
We will serve the Corps until the end!"
Oyakata-Sama's frail hands trembled, emotion welling in his eyes. He smiled warmly.
"I am proud of you… My children…"
After some time.
The crowd had dispersed. Hope had been rekindled.
But Ai Hanako walked alone through the silent courtyard of the Ubuyashiki mansion, her eyes distant, her thoughts storming.
"I'm glad I could reignite their will to fight… but this is just the beginning."
Her footsteps echoed softly along the stone path.
"I didn't sleep last night. I stayed up reading… searching. Desperate to understand the threats ahead of us."
She clenched her haori close as a chill breeze passed.
"Yoriichi Tsugikuni... He wasn't just a slayer. He was a force of nature. A man whose blade danced like the sun itself. And yet…"
Her pace slowed.
"When I look at Hajime-san… the way he moves, the aura he gives off—it's the same. Exactly the same. As if… he is Yoriichi."
She finally reached the Butterfly Mansion and slipped inside without a word.
The hallways were quiet.
When she entered her room, the scent of old pages greeted her. Her desk was buried under stacks of ancient books, texts on the history of the Demon Slayer Corps, volumes on Hashiras long gone, and forbidden scrolls rarely touched.
Without removing her haori, she sat at the desk.
The candle beside her flickered as she opened the topmost book. Her eyes scanned the title.
"Twin Shadows: The Tale of Yoriichi and Michikatsu."
She murmured, "If I want to understand Michikatsu… I have to start here. I need to know how the Moon Hashira fell."
She turned the pages.
Time slipped away, one hour into the next.
Outside, night deepened.
Cicadas stopped singing. The wind turned colder.
The candle burned lower.
By the time she turned the final page of the last book, it was already midnight.
She leaned back, stretching her arms, her shoulders stiff and sore.
"So much history… I've read everything—from the Heian Era till now, from the rise of Muzan to the battle that nearly ended the Corps. And yet…"
She rose from the desk and stepped toward the window, her violet eyes lifting to the glowing moon.
"…I still don't understand him… Michikatsu. I know who he was—a brother, a warrior, a Hashira. But not who he became. No record says anything after his fall."
She rested a hand against the cold windowpane.
"And what about the others? That shadow… the angelic figure… X… There's no trace of them in any official record."
Her breath fogged the glass.
A sudden jolt tore through Ai's spine like a lightning strike.
Her breath hitched.
"The drawings… something's wrong."
She rushed out of her room, the silent halls of the Butterfly Mansion blurring around her as she sprinted into the darkness outside.
The moonlight barely touched the earth, and even the insects had gone silent—swallowed by the eerie stillness of the night.
She stopped only when she reached the clearing.
There they were—etched into the dirt—
Six ancient drawings.
The wind stirred as she stepped forward. Her eyes locked onto the one that stood apart—the shadowed figure sketched in jagged black strokes. Its form was inhuman. Faceless. Crawling with something vile.
Her pulse quickened.
"This one… This is different. It's not just disturbing… it feels cursed."
She crouched, eyes narrowing.
"Michikatsu… Muzan… Akaza and Douma—I've read about them. They're monsters, but at least they're known. But this thing—this one… and the girl…"
Her hand slowly moved to her hilt, fingers twitching as if her body resisted the motion. A faint tremor rattled her arm.
"It has to be either her… or this. And judging by the whispers I keep hearing in my sleep… it's this."
She took a deep breath, summoning every ounce of her courage.
Her blade flashed in the moonlight—
SLASH!
She sliced straight through the shadowy entity's face.
Silence.
Then—
SPLASH.
Warm crimson splattered across her face and uniform. Her katana dripped with fresh blood.
Her eyes widened.
"B-Blood?!" she gasped, staggering back. "How—how is that possible?!"
Suddenly, the earth trembled beneath her feet.
Her surroundings warped—the hideout vanished.
She was no longer outside the Butterfly Mansion. The trees disappeared. The world itself twisted into a void of blackness, the ground a sea of shadows beneath her.
And then—they emerged.
From the ancient drawings, five figures began to rise. One after another, they peeled off the ground like spirits from a tomb.
Akaza.
Douma.
Muzan.
Kokushibo.
Eliza.
They stood tall and silent, towering above their respective drawings—but their faces were blank, erased, like porcelain masks without eyes or mouths. They didn't move, yet their presence suffocated her like an ocean crushing a bird.
Her legs weakened. "W-What is this… a dream?! A vision?!"
She turned toward the fifth figure—Kokushibo.
He was… imposing. Towering. Familiar.
Her eyes widened. "Michikatsu… So this is him. He really looks like—like Yoriichi. They're… twins…"
The closer she stepped, the heavier the air became.
She staggered back, gasping.
"Even in silence… he's terrifying."
Then she turned—drawn by something unnatural.
Eliza.
Her beauty was divine. Unreachable. A being sculpted from light and elegance. Ai approached, awe-struck.
"She's too perfect. She doesn't belong in this world. Her body… her presence… like a goddess."
But even she—like the others—had no face.
Ai whispered, "Are you X…?"
Then—
A wave of dread.
The air behind her shifted. Bent.
She felt it before she turned. The soundless breath. The crushing pressure. The way her skin crawled.
She turned.
And saw him.
At a distance, half-submerged in the shadow, stood a silhouette.
Tall. Still. Unmoving.
His eyes—two glowing crimson orbs—lit the darkness like lanterns from the abyss.
Jigen.
She staggered backward, her breath caught in her throat, her katana trembling in her grasp.
"That… that's no illusion," she whispered, her voice cracking. "Is it… a demon? Made of pure shadow?"
Her mind raced, piecing together fragments of whispers, rumors, and haunted testimonies.
"Yamamoto-kun saw something like this… Yushiro-San too… they all described him—the one they couldn't name. The one who didn't leave a scent… didn't cast a shadow… Just a presence. A curse.
He's the one.
He's X!"
The shadow stirred.
Then, he moved.
No footsteps. No sound.
Just deliberate, graceful motion—as if the darkness itself bent to his will.
And with each step, he changed.
The writhing mass of shadow condensed into form—into a man. Young, composed, yet ancient beyond comprehension.
His obsidian hair flowed like ink spilled in slow motion, brushing the air around his pale, glowing skin. His robes dragged across the ground like a mourning shroud.
And his eyes—crimson, radiant, bottomless—gazed not at her, but through her.
Ai couldn't speak. Couldn't move.
Then—
With a sickening hum, an enormous crimson blade emerged—grown from his hand. It pulsed like something alive, forged from blood and torment.
He kept walking.
Step.
Step.
Then—
He vanished.
"Huh?!"
Her body tensed instinctively.
Swoosh!
A gust of wind rushed past her. Her breath froze.
She turned—
Too late.
In a flash—
SLICED.
Her vision spun violently. She could see her own body falling.
"My… head?!"
Then—
Darkness.
.
..
…
GASP!
Ai jolted awake, drenched in sweat, her chest heaving violently. Her skin was ice-cold.
"What was that…?" she breathed. "A vision? A nightmare? Or… a warning?"
She looked around.
The ancient drawings were gone.
The night was still.
But something was there.
Her gaze dropped—To the dirt below.
An ancient book lay at her feet, its leather cover cracked with age. Its presence was impossible—unholy.
She hesitated.
Then knelt, hands trembling, and picked it up.
The moment her fingers touched the surface, the pages glowed faintly with white light—like fireflies trapped in ink.
She opened it.
Her eyes widened.
"These… these are records. The story of Michikatsu… after he became a demon."
But there was no author.
No signature.
No scent.
No trace.
"Who… who could've written this? Who could've possibly known I was searching for this exact knowledge?"
And then it hit her.
"X."
Her hands trembled harder.
"Everything I saw… it was real. He showed himself to me. Not to kill me. But to give me… this."
Her lips parted. "But… why?
He knows I'm looking for the truth… But how? Does he see my thoughts? Is he… testing me?"
She closed the book, holding it close to her chest.
"I can't show this to anyone. Not even Oyakata-Sama. If X gave me this… he must know everything I do. And if anyone else tries to read it—
He might kill them."
She looked up at the night sky, but the stars were gone.
Only the moon remained. Watching. Waiting.
"…Thank you," she whispered to the air.
"But you're not like the others. You're not a demon, or a god.
You're something else."
———————————————————————
In the Infinity Castle.
A cold silence blanketed the colossal chamber—an endless cathedral of stone pillars spiraling toward a ceiling.
In the center of it all, beneath the dim glow of a blood-red lantern, Jigen knelt.
His silhouette flickered at the edges, as if made of living shadow. Darkness bled from his back and pooled on the floor like ink in water.
"Kokushibo-sama…" Jigen spoke, his voice low, deep. "What are your orders regarding the Demon Slayer Corps?"
"They are not the true threat."
A towering figure emerged slowly from behind the stone pillars—Kokushibo.
Six eyes glowing faintly, his hair cascading down like midnight silk, and his blade resting idly at his side.
"It is not the Corps… It is him…
Yoriichi."
The name hung in the air like poison.
"Let the slayers grow stronger. I want them to be at their strongest before I kill them…"
Jigen did not move. "I think the same."
Then—silently.
He rose.
He began to walk away, his figure trailing black mist behind him.
"Eliza must not know I saw Ai Hanako," he thought. "If she finds out… nobody knows what she might do."
But just as his body began to vanish into the walls of the castle—
"Jigen."
Kokushibo's voice was calm, yet final.
Jigen paused, the mist around him stilling.
They stood back-to-back. One, a living shadow. The other, a monument of ancient wrath.
"Tell me…" Kokushibo said. "How strong are the demon slayers?"
Jigen replied without turning.
"Compared to us…
They are mere insects."
But Kokushibo turned slightly, one of his six eyes glinting, "Anyone… among them might be a threat to us?"
After a long pause, he says. "Other than the primary threat, Yoriichi…
Only four might potentially be threats:
Ai Hanako, the Flower Hashira.
Kenzo Fuji, the Stone Hashira.
Chikafusa Yamamoto, another Sun Breathing user.
Kasumi Matsunaga, Yoriichi's biggest supporter. The Mist Breathing User."
Kokushibo turned fully now, the room seeming to darken around his presence.
"Descriptions alone are sufficient to mark them as threats. Especially… the boy with Sun Breathing."
Jigen tilted his head slightly, as if thinking.
Then spoke again.
"Four of them are dangerous… But if I had to say who is the strongest…"
He turned his head slightly, his eyes glowing red in the shadows.
"…It's the Stone Hashira."
Kokushibo's brow lifted.
Jigen stepped forward one more time. "I have not seen his strength. No one has. Not even the Twelve Kizuki. He holds it in—completely."
He turned to face Kokushibo, eyes locked.
"Based on my own calculations…
There is a 99.99% certainty that Kenzo Fuji is as strong as you once were, Michikatsu Tsugikuni—the second strongest human to have ever lived."