Morning light had just crossed the threshold of the base when Tomioka Giyu received an urgent dispatch from the Kakushi team.
—In the northern border, Kirigakure Village had lost over thirty people in just three days.
Scouts reported traces of a possible demon outside the village, and two Demon Slayer Corps members had gone missing. He was ordered to head there immediately.
"Sensei, will you come back for dinner tonight?"
Tō stood by the door, holding his freshly polished Nichirin Sword, his eyes filled with quiet expectation.
Giyu bent down and ruffled his hair, slipping the folded order into his uniform. "I will. Once I'm done, I'll come back. You and Tanjiro keep practicing your sword forms at home."
The next second, Giyu's figure vanished from sight.
Kirigakure Village sat deep at the base of a mountain, rarely visited by outsiders.
By the time Giyu arrived, the sun had just set. The whole village was silent—no voices, not even the bark of a dog.
The moment he stepped into the village, a thick, overwhelming stench of blood filled his nose. It was heavier than any he had ever smelled before, mixed with a suffocating pressure that instantly tightened every muscle in his body.
He followed the narrow dirt path inward. Most of the thatched houses had broken doors and shattered windows. Old, torn clothes lay scattered along the roadside, and here and there, patches of blackish-red blood had dried long ago.
When he reached the open square at the village center, his steps halted abruptly.
Two broken Nichirin Swords were thrust into the ground, the blades still stained with black blood—clearly the weapons of the missing Corps members.
"Are they from the Corps?"
A deep, metallic voice came from above.
Giyu jerked his head up. Atop the withered locust tree near the entrance stood a tall figure.
Moonlight spilled across the man's form, revealing six eyes embedded in his pale face.
In the center pair of eyes, the kanji for "Upper Moon One" were clearly carved within the pupils.
He wore the attire of a samurai from the Sengoku era—deep purple robes over black hakama, the hem stained faintly with dark red. His long black-and-red hair hung loosely over his shoulders.
In his hand, he held a narrow Nichirin Blade, its sheath engraved with intricate moon patterns that exuded a suffocating killing aura.
Upper Moon One—Kokushibo.
Giyu's heart clenched violently. His breath hitched—the pressure radiating from Kokushibo's body was crushing.
It was stronger than any demon he had ever faced—except Muzan himself.
It was like an invisible mountain pressing down on his chest, heavy enough to make even moving a finger feel impossible.
This was absolute dominance—the clear boundary between life and death.
Kokushibo descended slowly from the tree, his steps light as falling feathers, yet the ground quivered faintly beneath his feet.
He glanced at Giyu's Nichirin Sword and his deep-blue haori, then at the aura faintly rising from his body.
"So, you're a Hashira?"
Giyu said nothing, his mind racing. He knew clearly that Kokushibo was far beyond what he could handle alone.
Even with power greater than his past life, even with mastery over four breathing styles, against such overwhelming strength—it was meaningless.
He had to escape.
He had to report to headquarters and call for the other Hashira.
The instant he turned, Kokushibo's six eyes gleamed with faint amusement.
"Trying to run?"
Kokushibo slowly drew his blade. The moment the steel left its sheath, a cold wave of killing intent swept through the entire village.
"It's been a while since I've met a Hashira who actually tried to flee in front of me."
Because the others had been cut down before they could.
He didn't move much—just raised his wrist and swung casually. No breathing form, no wasted effort.
A sharp tearing sound sliced through the night.
Giyu saw only a flash of light before instinct forced him to dive sideways.
At that same moment, three nearby thatched huts—and the old locust tree—were cleaved cleanly in half.
The cuts were so smooth they looked measured with a ruler. Dust and splinters burst into the air.
Lying flat on the ground, cold sweat soaked through Giyu's haori. If his reaction had been half a second slower, he would have been sliced in two.
That strike—its speed and power—was beyond comprehension. It was true invincibility.
"You actually dodged?"
Kokushibo arched a brow. A flicker of surprise glimmered across his six eyes.
"So you're stronger than the insects I've killed before. No wonder you made it to Hashira."
Giyu pushed himself up, gripping his Nichirin Sword tightly. Pale-blue ripples shimmered along the blade.
"Water Breathing, Third Form: Flowing Dance!"
The sword light was smooth yet swift, aiming straight for Kokushibo's chest.
But Kokushibo didn't move an inch.
He simply twisted his wrist, and his blade intercepted Giyu's strike with effortless precision.
With a loud clang, Giyu felt a crushing force strike his blade. His arm went numb instantly, and his Nichirin Sword almost flew from his grip.
"Water Breathing, huh? How nostalgic."
Kokushibo's voice was calm as ever. With a flick of his wrist, he knocked Giyu's sword aside.
"Show me something real, or you'll die in a boring way."
Giyu drew a deep breath. His rhythm shifted in an instant.
The soft blue water pattern around his blade turned into a sharp, pale green current. "Wind Breathing, Third Form: Clear Storm Wind Tree!"
The sword light surged like a raging gale, cutting toward Kokushibo's limbs at unpredictable angles.
Kokushibo parried easily, every block precise. He even found time to tap Giyu's shoulder with the back of his blade, as if toying with prey.
"Wind Breathing? So you can use multiple breathing styles?"
His six eyes flickered with faint curiosity.
"You've got some talent."
Giyu ignored the taunt and changed his breathing once more.
Flames of orange and red flared across the blade. "Flame Breathing, Third Form: Blazing Universe!"
The burning strike roared through the wind, slashing straight for Kokushibo's neck.
Kokushibo tilted his body slightly, letting the attack slip past. The blade tore open Giyu's haori, leaving a long rip down the fabric.
"Flame Breathing… that makes three."
A glint of appreciation flashed across Kokushibo's six eyes.
"Tell me your name, Hashira."
Giyu didn't respond. He knew none of the standard Breathing Styles could hurt this monster.
He inhaled deeply again, his breath turning hot and divine. A golden radiance spread along the blade—his final card.
"Sun Breathing, Second Form: Clear Blue Sky!"
The golden slash shone like the midday sun, carrying the aura of destruction itself as it pierced toward Kokushibo's chest.
Kokushibo's pupils constricted, and for the first time, true shock filled all six eyes.
That Breathing… that sword form—he knew it all too well.
It was Yoriichi's Sun Breathing—the technique he had chased for a thousand years, yet could never surpass.
For an instant, he froze.
The golden blade light struck, tearing through his robe and leaving a shallow cut across his chest.
"You… can use Sun Breathing?!"
Kokushibo snapped out of his daze, his eyes igniting with a storm of fury—and something else, a manic excitement.
He stopped holding back. His aura erupted, black mist swirling around his blade as cold moonlight filled the air.
"Moon Breathing, First Form: Dark Moon, Evening Palace!"
The black sword light glided like a phantom beneath the moon, ripping through the air with terrifying force, and struck Giyu square in the chest.
"—Ghkk!"
Even though Giyu raised his sword to block, blood burst from his mouth as his body was flung backward like a severed kite.
He crashed into a half-collapsed wall, shattering it completely.
When he tried to rise, searing pain tore through his chest. At least three ribs were broken. His Nichirin Sword had fallen a few meters away, and even moving his fingers took effort.
Kokushibo approached slowly, towering over him. The light in his six eyes flickered with mixed emotion—murder, surprise, and a growing, obsessive fascination.
For a thousand years, beyond the games of Go and the thrill of battle, this was the first time someone had truly piqued his interest.
"Tell me… how do you know Sun Breathing?"
Kokushibo's deep voice trembled slightly, betraying what he tried to hide.
"This technique… this sword style… Muzan-sama and I destroyed every trace of it, every person who ever knew it. Where did you learn it?"
Unbidden, the image of Tsugikuni Yoriichi surfaced in his mind—the man in the red haori, sword in hand, who even in his final breath had pushed Kokushibo to the brink of death.
The man he could never surpass.
And now, the swordsman before him—far weaker, yet wielding that same light—made him feel both furious and ecstatic.
"You… are truly interesting."
Kokushibo crouched down, dragging a fingertip gently across the wound on Giyu's chest, his gaze darkening with twisted fascination.
"So weak, yet carrying such a rare and precious breathing form."
Giyu clenched his teeth, saying nothing, but he could sense something dangerous brewing in those six eyes.
"Tell me, Hashira… do you want to become a demon?"