"Kokushibo…" Ren murmured. "Lord Muzan, I don't question your decision, but I believe the Upper Rank titles are misordered. The Twelve Kizuki is your legion, and only the strongest should lead. How else can they command respect?"
Muzan's eyes gleamed. "Ren, you wish to challenge Kokushibo?"
Ren's intent was clear, and Muzan understood perfectly.
"Yes," Ren said calmly. "Since you've formed the Twelve Kizuki, I will vie for the top."
"Very well. If that's your desire, I'll allow it," Muzan replied.
Muzan disliked infighting among his demons, viewing them as his possessions. Their conflicts wasted her resources. But Ren and Kokushibo were exceptions.
Capable subordinates who eased his burdens were always valued, and Muzan was no different.
For such underlings, he showed patience and leniency. As long as their requests weren't excessive, he wouldn't object.
Truthfully, Ren's challenge intrigued him.
Though he turned Ren into a demon and held absolute control over them, he didn't fully grasp his true strength.
This duel would reveal his subordinate's capabilities.
Muzan glanced aside. A screen slid open, revealing a figure seated impassively.
His face was grotesque, adorned with six eyes. A long sword rested before him, his gaze calm, as if nothing stirred his interest.
Kokushibo, once a Demon Slayer, Yoriichi Tsugikuni's brother, Michikatsu Tsugikuni.
Seeing him, Ren's emotions subtly shifted.
"Kokushibo, did you hear Ren's words?" Muzan asked.
"I understand. When does the duel begin?" Kokushibo replied, his words brief.
"No need to wait," Ren said. "Now."
In a desolate mountain, devoid of human presence but teeming with beasts, they found a perfect battleground.
Muzan stood between Ren and Kokushibo. "I will decide the victor, unless one yields first. Understood?"
"Yes," Ren said.
Kokushibo nodded silently.
"Then begin," Muzan declared.
The duel commenced, yet neither Ren nor Kokushibo moved immediately.
"Uncle," Ren said, addressing Kokushibo, his calm eyes hiding a storm. "You betrayed the Demon Slayer Corps and killed Ubuyashiki. Why didn't you slay the Hashira too?"
Kokushibo remained silent, unsure of Ren's intent.
"Human affairs no longer concern me as a demon," he said.
"Reasonable, but it's merely an excuse for your incompetence," Ren retorted. "Had I become a demon first, the Corps would be ashes."
Kokushibo's brow twitched, his six eyes fixing on Ren.
"An unworthy man doesn't deserve his place. Are you ready?" Ren asked softly, reaching for his shoulder.
The crow on his shoulder opened its beak, spitting out a sword hilt from its gullet.
Ren grasped it, drawing a long blade slowly from the crow's mouth.
The blade was blood-red, its surface bristling with sharp, jagged spikes like a demon's fangs. Closer inspection revealed the spikes writhing, as if alive, ready to break free and lunge at foes.
Kokushibo, silent until now, fixed his gaze on Ren's blade. A chilling night breeze swept through, lifting his cascading black hair.
But more striking was the vivid red that flashed into Kokushibo's vision.
"Crow Breathing, First Form: Blood Crow · Kyoto Dance!"
With Ren's soft cry, time seemed to freeze.
In a blink, the faint red exploded, swelling rapidly in Kokushibo's sight.
Instantly, countless blood-red crows surged forth, blotting out the sky, sealing Kokushibo's vision.
Even with six eyes, he was blind to all but crimson.
This thick, blood-like sea enveloped him, a net trapping him in chaos and disarray.
Kokushibo moved, his arm muscles bulging as he gripped his sword. "Moon Breathing, First Form: Dark Moon · Evening Palace!"
Two demons, Muzan's mightiest, clashed not with Blood Demon Arts but with swordsman's blades!
Their strikes collided, crows scattering, crimson cloaking the sky. Kokushibo's face showed no emotion, his eyes devoid of feeling as he swung again.
"Moon Breathing, Second Form: Pearl Flower Moongazing!"
Two slashes arced toward Ren, surrounded by countless tiny crescent blades. Moon Breathing, Kokushibo's creation, featured these crescents—disruptive, chaotic, and hard to counter. Though less destructive, they were relentless.
These crescents countered Ren's blood crows perfectly.
Yet Ren stood motionless, letting the attacks strike him.
Muzan frowned nearby.
Demons' regenerative abilities meant wounds healed instantly. Without sunlight, neither Ren nor Kokushibo could die.
Muzan had declared he'd judge the victor, as only a death match until dawn could otherwise settle it.
In his eyes, Ren's passivity was a misstep.
Unbeknownst to Muzan, Ren had planned everything before the duel began.
Michikatsu Tsugikuni, Yoriichi's brother, Ren's former uncle, now Kokushibo—Ren harbored unspeakable emotions toward him.
Chitoshi's death stemmed from Kokushibo's actions. Had he not killed Ubuyashiki, the subsequent tragedies wouldn't have unfolded.
Yet, as a demon, Ren's perspective had shifted.
He didn't hate Kokushibo for killing Ubuyashiki. He hated his half-measures—why spare the Hashira?
Had he slain them, would Chitoshi have died?
Without those vile pillars, Chitoshi might have lived.
If you're so incompetent, what right do you have to stand above me?
Are you worthy?