Timeline: Three years before the main story
Location: Kamado Mountain
POV: Split (Akira / Giyu / Muzan)
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Akira
The moment stretched.
Muzan stood before him, body restored, expression twisted between fury and disbelief. His regeneration was perfect — yet his movements carried hesitation.
Akira inhaled.
And the world opened.
The Transparent World unfolded around him, colors draining away, flesh becoming structure, motion turning into intent. Muzan's body revealed itself fully.
Seven hearts.
Five brains.
All moving.
Akira stepped forward.
Hinokami Kagura — Thirteenth Form.
There was no flourish.
Only motion without gaps.
The blade burned crimson, heat compressed so tightly it did not flare outward. Akira moved in a continuous flow, never stopping, never repeating the same angle twice.
The first heart shattered.
Then another.
Then a brain.
Muzan screamed as his body spasmed violently, regeneration stalling for the first time that night.
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Muzan
Impossible.
This was not imitation.
This was execution.
Every strike arrived before his cells could react. The boy wasn't chasing him — he was dismantling him.
"No—!" Muzan snarled, launching tendrils in every direction.
They missed.
Akira was already inside his guard.
Another brain destroyed.
Another heart crushed.
Panic eclipsed rage.
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Giyu
Water Breathing surged as Giyu arrived in a blur of motion.
He took in the scene in a single breath.
Muzan wounded.
The forest burned away in perfect arcs.
Akira moving like a living sun.
There was no hesitation.
Water Breathing — Eleventh Form: Dead Calm.
Giyu entered the battle, blade intercepting Muzan's counterattack that would have pierced Akira's flank.
Steel rang.
"Akira," Giyu said calmly. "I'll cover."
Akira nodded once.
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Akira & Giyu
They moved together without planning.
Sun and water.
Pressure and flow.
Muzan was forced back step by step, his attacks parried, redirected, burned away. Akira's blade struck with lethal precision while Giyu erased openings before they could be exploited.
Another heart destroyed.
Another brain crushed.
Muzan staggered, regeneration tearing his body apart as fast as it rebuilt it.
He was cornered.
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Muzan
Fear ruled him now.
True fear.
His body was failing to synchronize. His mind fractured under overlapping memories — flame, crimson, eyes that saw through everything.
"This cannot happen again," Muzan hissed.
He lashed out desperately.
Giyu moved to intercept—
Too late.
Blades of flesh pierced through Giyu's side and shoulder, ripping deep before Akira severed them instantly. Blood spilled onto the snow.
Giyu fell to one knee, breathing ragged but conscious.
Akira stepped forward.
The thirteenth form never stopped.
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Arrival
Shockwaves rippled through the forest.
Sanemi crashed through the trees, killing intent roaring.
Gyomei followed, earth trembling beneath his steps.
Kanae arrived moments later, eyes wide at the sight before her.
"Muzan," Sanemi growled. "You bastard."
For the first time, Muzan looked surrounded.
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Intervention
The sound cut through everything.
A single biwa string.
The world warped.
Space folded violently as shadows swallowed Muzan's body.
Nakime's power tore him away mid-regeneration, flesh still burning where the crimson blade had struck.
Muzan vanished — screaming in rage.
Silence crashed down.
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Aftermath
Akira extinguished the heat in his blade and turned immediately to Giyu.
He knelt, hands steady.
"Deep breaths," Akira said. "You're not dying."
Giyu nodded, teeth clenched, pain sharp but controlled.
The other Hashira stood frozen, staring at Akira — at the scorched battlefield, at the impossible wounds Muzan had suffered.
Kanae whispered, "You… nearly killed him."
Akira looked toward the space where Muzan had disappeared.
"…He ran," Akira said calmly. "That's enough for tonight."
The Sun dimmed.
But it did not set.
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