Flame Hashira: Rengoku Kyojuro!
Water Hashira: Tomioka Giyu!
Insect Hashira: Kocho Shinobu!
Serpent Hashira: Iguro Obanai!
Wind Hashira: Shinazugawa Sanemi!
Stone Hashira: Himejima Gyomei!
Demon Slayer Corps Master: Ubuyashiki Kagaya!
And finally—our protagonist: Kamado Chika!
The room was filled with the most powerful figures of the Corps.
At the center sat Rengoku and Chika, closest to the Master.
Closer still—laid before the Master—were their swords.
Ubuyashiki leaned forward, his cloudy eyes widening in awe.
"They've… truly changed. How incredible…"
Even with his calm composure, he was visibly shaken. The archives of the Ubuyashiki family were vast, recording every known phenomenon about demons and the blades forged to kill them. Yet in all those generations—there had never been a single mention of this.
Not one.
He turned to the assembled Hashira. "What do you all think?"
Though none of them were swordsmiths, each was a veteran warrior who'd lived and killed by the Nichirin Blade. If anyone could sense its mysteries, it was them.
"The blades reached such high heat through constant collision," began Iguro Obanai, his mismatched eyes narrowing as his snake coiled tighter around his shoulders. "Nichirin steel is forged from minerals that absorb sunlight. If this heat has amplified that solar essence… then these blades must be even deadlier to demons."
He spoke with quiet conviction. His heightened senses could feel it—an intensity radiating from the blades that surpassed anything before.
"I agree," said Kocho Shinobu, tapping her chin with a gloved finger. "But before we conclude anything, perhaps we should test it. Find a demon and see how it reacts to this kind of wound."
A murmur of approval circled the room.
Of course. They needed proof.
After all, the Red Blade—the Crimson Blade of Heat—wasn't permanent. It was born of temperature: when the Nichirin reached a heat that awakened the sun within its metal. Once cooled, it would fade back to its original color.
Under Ubuyashiki's measured command, a formal series of experiments began.
First: replication.
Pairs of Hashira took to the training grounds, mimicking the duel between Rengoku and Chika. Their goal—to trigger the Red Blade through repeated high-impact clashes.
Sparks filled the air. Metal sang.
By the end, every Hashira except Shinobu had managed to awaken their Red Blade.
Her strength simply wasn't suited for such a brute-force approach—but the others had done it. The phenomenon was real, not coincidence.
Then came Phase Two—testing its power.
In a narrow alley of a provincial town, a terrified demon fled for its life.
It wasn't hunting.
It was being hunted.
Behind it, Shinazugawa Sanemi charged like a white-haired storm, his face twisted into something even fiercer than the demon's.
"Wind Breathing, First Form: Dust Whirlwind Cutter!"
His body blurred—a tornado given human shape.
In an instant, he passed the demon. A flash of steel followed by silence.
Then—thud.
The creature stumbled, shrieking, staring in horror at its severed arms lying on the cobblestones.
Normally, such wounds were trivial. A few seconds, and the limbs would regenerate. But this time—nothing.
The stumps smoked, charred. The pain didn't fade—it grew worse.
"W-Why… why can't I heal?! It hurts—it hurts so—!"
Shff!
One clean upward slash ended its cries.
The body turned to ash, scattering into the wind.
Sanemi exhaled slowly, a rare grin tugging at his lips. He could feel it—the weapon still burning in his hand.
The experiment was a success.
Three days later, the results were clear.
Sanemi's report confirmed it beyond doubt: the Red Blade nullified a demon's regeneration.
Cheers broke out among the Hashira. Even Ubuyashiki's frail frame seemed to tremble with joy.
A weapon that not only increased damage—but erased the enemy's greatest advantage.
It was a miracle.
Of course, they didn't let excitement blind them to flaws.
Weaknesses of the Red Blade:
Its duration was limited—the heat faded with time.
Activating it required sustained collisions, impractical in real combat.
As murmurs of thought filled the chamber, Chika raised her hand.
"What if," she said lightly, "we try grip strength?"
The room fell silent.
"…Grip strength?" repeated Shinobu, blinking.
"Like… squeezing the hilt?" murmured Obanai.
Sanemi frowned. "You mean heating it up by… holding it tighter?"
Chika's smile stayed polite, but the sweat drop was almost visible.
'Yeah, I know how it sounds,' she thought dryly. 'But that's literally how it worked in the source material…'
If she weren't worried her own grip strength wasn't enough yet, she would've just demonstrated it herself.
In the original timeline, both the Serpent and Mist Hashira had awakened their Red Blades this way—pure grip pressure, enhanced by their Marks.
But here, no one had their Marks yet. Would it still work? Even Chika wasn't sure.
Then—someone stood up.
A towering figure, rosary beads clinking softly as he moved.
Himejima Gyomei.
The Stone Hashira.
The strongest Demon Slayer alive.
The man whom Upper Moon One himself had called "the strongest human body in three hundred years."
"Allow me to test this method."
No one objected.
If the Stone Hashira couldn't do it, no one could.
He stepped forward, the floorboards creaking beneath his enormous frame, and drew his weapon.
Unlike the others, Gyomei's Nichirin weapon wasn't a sword at all.
With a metallic clatter, he unfurled it—a heavy chain, one end a gleaming axe, the other a spiked flail larger than his head.
The air thickened with tension as the others watched in silence.
Would the strongest man in the Corps…
truly awaken the Red Blade with his bare hands?