The sudden blade light cut off Shōkyū's Blood Demon Art.
Sensing the familiar aura within that bluish-green slash, a playful gleam flashed through Shōkyū's crimson eyes, and he slowly looked up.
Sure enough, not far away, atop the ruined attic, Shinichi stood with his blade in hand.
Bluish-green light flowed along the edge of his Nichirin sword, and his gaze passed over the demons surrounding Giyu Tomioka and Tengen Uzui before landing straight on Shōkyū.
There was no killing intent in those calm black eyes.
No anger.
Only a resolve so quiet it had reached its absolute limit.
Shōkyū was staring at Shinichi as well. In those crimson eyes, a trace of excitement churned, almost impossible to hide.
It was the excitement of a farmer who had spent ages carefully raising his crop and had finally reached harvest season.
He lazily lifted one claw.
In the next moment, the dozens of demons attacking Giyu and Tengen all froze at once.
Then, as though forced under some invisible control, they snarled and slowly backed away, leaving the two Hashira a little room to breathe.
But Shōkyū did not even glance at them.
"Well, Shinichi, you really are hard to kill." Shōkyū's voice was not loud, yet it rang out strangely clear through the demons' roars.
His mouth split open, revealing sharp fangs.
"Even that legendary strongest swordsman couldn't kill you? Tsugikuni Yoriichi… I suppose titles really can't be trusted. I went out of my way to drag him up from Yomi, and he couldn't even deal with a brat."
Shinichi did not answer.
His gaze shifted away from Shōkyū and fell on Giyu Tomioka and Tengen Uzui below.
Giyu's left arm hung weakly at his side.
Blood dripped down from it, gathering into a small pool on the ground.
His Nichirin blade was stabbed into the floor, and the water-blue light on its edge had grown so faint it was almost invisible.
Tengen was in even worse shape. Of his twin blades, only one remained; the other had broken somewhere along the way.
A deep wound cut across his chest, so severe that bone could be seen, and every breath he took came with flecks of blood.
Shinichi leaped down from the ruined attic and immediately placed his hands on their shoulders. Bluish-green light flowed from his palms into their bodies.
Both men let out muffled groans, and their bodies, which had been on the verge of collapse, finally gained a little breathing room.
"That's enough, Shinichi."
Giyu pushed himself up with his sword. His voice was still cool, but there was a rare trace of concern in it.
He pushed Shinichi's hand away and shook his head.
"Save your strength for that thing. Wounds like these won't kill me."
Tengen also used his remaining blade to support himself.
He grinned, showing bloodstained teeth.
"I'm not so pathetic that I need to lie down and be saved yet. I'm going to show that bastard what real flamboyance looks like!"
Shinichi looked at the two of them.
After confirming they were not in immediate danger of dying, he nodded.
Then he stood and walked in front of them, facing Shōkyū and the surrounding demons directly before striding toward Shōkyū.
And as Shinichi advanced, the demons around him actually kept backing away, as if they had no intention of stopping him at all.
Black eyes met crimson eyes in midair.
The air seemed to freeze.
The roars of the demons became faint and blurred.
Shinichi could no longer hear them, in his eyes and ears, only that figure remained.
Shōkyū was the same.
Two "foreigners" who had returned from Yomi continued walking toward each other.
At last, Shinichi stopped.
There were only a few dozen steps between him and Shōkyū, but that distance had become the boundary between life and death.
"You should know," Shinichi said under Shōkyū's amused gaze. "Or rather, we both should know. The two of us can only die by each other's hands."
Shōkyū's pupils contracted slightly.
That crimson glow flickered in the darkness, as if something had stung him.
Shinichi continued, his voice calm and steady, each word spoken clearly.
"Judging from your face, I guessed right. The power of Yomi you've been dreaming of can only be fully controlled after you truly kill me. That's also why you summoned Yoriichi from Yomi but didn't forcefully control him, isn't it? You needed him to test my strength. You needed him to push me to grow. You needed me to become strong enough that, when you killed me, you could draw enough power from my 'life force' to control Yomi."
Shinichi paused briefly.
"Because you know that only by killing a strong enough opponent can the power of Yomi inside you truly awaken. You need someone like you—someone who returned from Yomi. You need me. From the very beginning, you've needed me. Isn't that right, Shōkyū?"
Shōkyū's face darkened little by little.
The curve of his smile vanished, replaced by a cold snort.
"Hmph. Not bad."
Shōkyū spread his claws.
Behind him, the thorn whips opened like a peacock's tail, and one hideous whip after another writhed through the air, hissing as they cut through the darkness like countless venomous snakes flicking their tongues.
"So what? Do you get a prize for guessing right? Do you really think you're my match? You're nothing but an ignorant brat in your teens. You think that can compare to the plans I've spent centuries building? You think seeing through everything changes anything? You have no idea how long I've prepared for this day!"
Clang!
The sound of a biwa rang out.
Then another.
Clang! Clang! Clang!
The space behind Shōkyū began to ripple violently. One twisted crack after another opened within the Infinity Castle.
Dim yellow light poured out from those rifts, carrying the stench of decay and death.
Demon after demon crawled out of the cracks. They snarled and roared, their crimson eyes flashing with bloodthirsty light in the darkness.
Their numbers kept growing.
From a dozen to several dozen.
From several dozen to over a hundred.
Soon, they filled Shinichi's entire field of vision, surging forward like black tides, wave after wave.
"The power of Yomi will be mine sooner or later!"
Shōkyū roared and swung his claws down.
"Go! Tear him apart! Tear all of them apart!"
The moment his command fell, countless demons let out deafening roars and charged madly toward Shinichi.
Shinichi looked at the overwhelming horde without retreating.
He lowered his body slightly, his feet spreading to shoulder width as his center of gravity sank.
Both hands gripped his Nichirin blade tightly, the cold touch of the hilt pressing into his palms.
He looked at the countless tiny chips along the blade.
"Old friend, once this battle is over, I'll definitely have Master Tetsushinren give you a proper tune-up."
As if sensing his words, the Nichirin blade gathered bluish-green light along its edge.
Shinichi's breathing became slow and deep.
The power of Life Breathing circulated through his body, and with every breath, he grew a little stronger.
Within the tide of demons, one demon with a sharp horn on its forehead charged the fastest.
It was larger than the others by a full size, its body covered in black scales. Its beast-like limbs left deep claw marks in the ground with every step.
Boom!
The horned demon opened its mouth, revealing rows of jagged teeth. A foul stench rushed toward Shinichi as it bit viciously for his throat.
Shinichi raised his Nichirin blade.
The bluish-green light on the edge blazed to its brightest point.
Then—
A blade light flashed past Shinichi's side.
It was not his blade.
It was a sudden slash from someone else.
The strike was not especially powerful. In fact, it could even be called weak.
But that blade light carried a momentum that refused to turn back, and it landed precisely on the horned demon's neck.
Pshk!
The sound of a blade cutting into flesh rang out clearly.
The horned demon's head flew high into the air. Dark-red blood sprayed from the severed neck, and the demon's body stiffened in midair before crashing heavily to the ground.
Shinichi was genuinely stunned.
He had not even processed what had happened.
A young Demon Slayer in a black uniform had already taken his place at Shinichi's side.
He held his Nichirin blade in both hands, water-blue ripples slowly spreading across the blade's surface.
His face was covered in blood and grime, and there was still an unhealed wound on his left arm, but his eyes were astonishingly bright.
"Forest Hashira-sama! We're here!"
The young swordsman's voice trembled, not from fear, but from excitement. The veins on his hands bulged as he gripped his sword, his knuckles turning white.
"Everyone, attack!!"
Shinichi looked at the young Demon Slayer.
There were many swordsmen in the Corps who used Water Breathing, so Shinichi could not possibly know every member, but the boy in front of him seemed strangely familiar.
Before Shinichi could remember his name, more blade lights lit up beside him.
One figure after another in black uniforms rushed past Shinichi, charging toward the endless horde of demons ahead.
Some of their faces were young, while others were weathered.
Some were covered in wounds, some streaked with tears.
But in their eyes, flames were burning!
"Kill them!!!"
"Charge!!!"
"For the Demon Slayer Corps! For the Master! For our fallen comrades!!!"
Their cries rose one after another like thunder shaking the Infinity Castle.
Dozens of them.
Then over a hundred.
They surged out from behind Shinichi and charged without hesitation toward that seemingly endless tide of demons.
Their Nichirin blades shone in the darkness with all kinds of light—water blue, emerald green, golden yellow—interweaving together in a dazzling brilliance.
Shinichi was not fighting alone.
He never had been.