"Every time I see your pretty face, I get angry."
Gyutaro's fingers clawed at his scarred skin, drawing thin lines of blood as his muscles flexed with barely restrained violence. He prepared to pounce on Doma like a predator sensing weakness in its prey.
"Are you sure you want to fight?" Doma's voice carried that characteristic musical quality, though something sharper lurked beneath the pleasant tones. "Your sister is in danger."
The words hit Gyutaro like a physical blow. He had taken exactly one step forward before freezing completely, his body trembling with the effort to stop in the middle of an attack. Even Kokushibo, who had been standing motionless beside Doma, turned his head to study the ice demon with calculating interest.
What was that bastard planning now?
"Huh, that trash... just her?" Before Gyutaro could process the implications, Daki's sneering voice cut through the tension like a blade. She gestured dismissively at the assembled heirs with a perfectly manicured hand. "Bunch of ugly guys."
The faces of the heirs darkened instantly, hostile gazes focused on the courtesan with laser intensity. Several hands drifted toward weapons, though none had yet drawn steel. They had come for Muzan's blood, not to be insulted by some vain demon's plaything.
But Daki's complete lack of concern only emphasized what everyone already knew - with Gyutaro protecting her, she could afford to antagonize anyone she pleased.
"Here they come," Kokushibo suddenly announced, his six eyes reflecting the moonlight as he sensed the approaching disturbance.
The ground beneath everyone's feet changed without warning. What had been solid earth became an ornate doorway that swung open with impossible smoothness, revealing a yawning void of absolute darkness below.
Every fighter except Doma and Kokushibo immediately moved to dodge, their survival instincts screaming warnings of dimensional traps and spatial manipulation. But Doma just smiled that infuriating smile and spread his arms wide.
"Let's go see Master Muzan," he said with cheerful anticipation, as if they were heading for a pleasant social gathering instead of what would likely be their death.
Without the slightest hesitation, the two former Upper Moons let themselves fall through the opening portal and vanished into the darkness as if they had never existed.
The Heirs hesitated, suspicious minds racing through the possibilities. Was this an elaborate trap that Doma had orchestrated from the beginning? Despite their apparent falling out with Muzan, it wasn't impossible that the three demons had secretly reconciled. Nothing in this twisted world was absolute, and the two traitors had once been the Demon King's most trusted subordinates.
This gathering represented the largest concentration of heirs in decades. If Muzan wanted to eliminate them all in one fell swoop, tonight would be the perfect opportunity.
"Come in."
The familiar voice resonated directly into the minds of several First Generation Inheritors, bypassing their ears entirely to speak directly to their souls.
Oboro.
The moment they heard this mental command, every trace of hesitation vanished. Daki and Gyutaro were the first to respond, jumping into the spatial portal without a backward glance. The older heirs followed immediately, their faith in their creator absolute and unshakable.
The younger generation-those who had risen in the chaos that followed the Edo period-exchanged uncertain glances. They knew the name and the legends, but most had never had direct contact with the God of Swordsmen himself.
Finally, gritting their teeth and steeling their resolve, they too plunged into the unknown.
Time and space twisted.
Several heartbeats later, as the disorienting sensation of dimensional travel finally faded, the assembled fighters found themselves separated and scattered across a series of floating platforms that defied logic and physics.
The architecture surrounding them was a fever dream of impossible geometry. Wooden buildings, elegant chambers and staircases hung in the air with no visible support, spreading through space as if gravity had become a mere suggestion rather than an absolute law.
This was a pocket dimension - the legendary Castle of Infinity, which served as Muzan's ultimate stronghold.
Before anyone could fully process their surroundings, a crushing spiritual pressure descended upon them like a mountain falling from the sky. The air itself grew thick and oppressive, saturated with a murderous intent that made breathing feel like drowning.
Every head turned toward the source of this overwhelming aura.
High above them, on a platform that seemed carved from polished obsidian, a figure gazed down with the cold calculation of a god watching insects. He wore an elegant black suit that fit his frame with tailored perfection, complemented by a top hat that cast deep shadows across his features. Beneath the brim, the familiar scarlet pupils gleamed with barely contained hatred, set in a face of cadaverous perfection.
Muzan Kibutsuji. The king of demons. The source of every horror that had plagued this world for over a thousand years.
But some of the more experienced heirs noticed something that made them gasp. Behind and above Muzan, sitting cross-legged on the highest platform in the room, another figure waited in silent observation.
Who could position himself above the Demon King himself?
Half of the assembled fighters did not recognize the man, but the distinctive black haori draped over his shoulders - identical to the one Gyutaro wore with such fierce pride - revealed his identity to those who knew the legends.
Oboro. The origin of their inherited will. The giver of soul power who had single-handedly changed the fundamental nature of this world. In the minds of many, he had already transcended mere mortality to become something almost divine.
Without hesitation, each Heir dropped to their knees and bowed deeply in Oboro's direction. They showed no respect for Muzan - their reverence was reserved for the man who had saved them from despair and given their lives meaning.
Muzan watched this display with a blank expression and said nothing. He understood perfectly where their loyalties lay, and the knowledge burned like acid in his chest.
Seeing the veterans prostrate themselves, the younger heirs quickly followed suit, unsure of the proper protocol but unwilling to show disrespect.
"Don't be so reserved," Oboro said gently, supporting his chin with one hand as the familiar smile played across his features. "This place is called the Castle of Infinity - it is Muzan's territory. I'm only a guest here today."
His gaze swept over the assembled faces, lingering on each with the loving attention of a craftsman examining his finest work. Except for a few unfamiliar Inheritors who had appeared during the post-Edo chaos, these people were all his creation. The unfamiliar faces represented second and third generation transformations, the legacy of first generation inheritors like Teshimagagaji and Yasuhara who had passed the gift on to others.
His blood had freed the original Inheritors from Muzan's control, but as they transformed others, that blood was diluted. The connection weakened with each generation, though the basic will remained intact.
"Ah, it's wonderful to see you again," the long-haired woman in the white kimono breathed, raising her head to reveal flushed cheeks framed by cascading hair. Her eyes shone with the devotion of a true believer gazing upon her deity.
"Ayako, you have become beautiful," Oboro remarked with genuine warmth.
"Really?" The woman immediately pressed both hands to her face, joy radiating from every pore like sunlight breaking through clouds.
"Yes."
There were always outliers among the Heirs. While Oboro had saved this group and inspired them to carry on his vision, some - like Ayako - weren't primarily motivated by grand dreams of reshaping the world. Her dedication stemmed more from personal devotion than ideological conviction. She would do anything to live up to Oboro's expectations, not because she believed in the cause, but because she believed in him.
Oboro didn't consider himself to be particularly charismatic. He suspected that some Inheritors developed this intense attachment because their human experiences had been so traumatic. When he appeared to save them in their lowest moment, they naturally imbued him with an almost divine significance.
"I am here today only as a witness," Oboro continued, his voice carrying to every corner of the vast room. "No matter who emerges victorious, this era will finally come to an end."
The intelligent ones among the assembled fighters immediately grasped the deeper meaning. They hadn't been brought to the Castle of Infinity because of Muzan's machinations or Doma's manipulations.
Everything - every move, every meeting, every confrontation - had been orchestrated by the man who sat in judgement over them all.
"Kill Muzan Kibutsuji," Oboro declared, his words falling like pronouncements of fate. "Claim the power of the Demons for the Heirs. You will achieve unprecedented growth and evolution, better positioned to usher in the era you deserve - a world that reflects your vision of what should be."
His attention shifted to the siblings. "Daki, Gyutaro... your task remains unchanged. Eliminate Doma and Kokushibo. This is the mission I entrusted to you both a long time ago."
Finally, his gaze settled on the Demon King himself. "And Muzan faces the greatest challenge of all. Not only must he purge the traitors who betrayed him, but he must survive every other enemy gathered here tonight. To him, you are all obstacles standing between him and the future he desires.
Oboro's expression became solemn as he spoke his last words. "I will not interfere in this battle. While some aspects of your destiny bear my influence, the choices that brought you to this moment were your own. You all have positions from which you cannot retreat, principles you cannot abandon. So fight with everything you have.
The moment he finished speaking, the tension in the room became almost unbearable. Warriors who had spent years or decades preparing for this confrontation felt their muscles tighten with anticipation. Hearts pounded against ribs as adrenaline flooded their nervous systems.
The war was about to begin.
Each teetered on the edge of life and death, ready to erupt into violence at the slightest provocation.
This would be chaos incarnate-a battle royale in which each participant held grudges against multiple enemies.
The person with the worst odds was undoubtedly Muzan. He stood alone against overwhelming odds, with only one fighter who could possibly ignore him: Gyutaro.
But even this slim hope was questionable. Muzan had hunted the scarred demon relentlessly over the past few years, and Gyutaro's memory for slights was legendary. If an opportunity to claim the Demon King's head presented itself, the mad dog would not hesitate to seize it.
"Don't forget what you promised me," Muzan said suddenly, turning to look at Oboro with desperate intensity.
If he somehow survived this nightmare and emerged victorious, Oboro would honor their agreement. No more interference, no more manipulation. The ultimate reward: transformation into a perfect life form, immune to every weakness that had defined his existence.
"Of course," Oboro replied with calm certainty.
The moment the confirmation left his lips, every figure on the floating platforms vanished in explosive bursts of movement.
But Muzan's mastery of the Castle of Infinity allowed him to manipulate dimensional space with surgical precision. When the chaos subsided, only one opponent remained on his platform.
Doma stood alone, still wearing that unbearable smile.
If Muzan hadn't acted quickly to separate his enemies, the Inheritors would have joined forces with Kokushibo and Doma immediately. The ice demon had orchestrated this gathering specifically to create such an alliance, knowing that their combined strength offered the only realistic chance of victory.
But Muzan refused to let this strategy succeed. If he were to die tonight, he would at least have the satisfaction of personally killing the traitor who had humiliated him the most.
"It turned out to be me," Doma laughed, showing not the slightest sign of concern despite his desperate situation. "Should I feel lucky or unlucky? I was hoping you'd choose Kokushibo instead."
Muzan had no patience for the ice demon's casual banter.
The platform beneath Doma's feet, solid as granite moments before, suddenly transformed into a writhing mass of flesh and blood. The organic matter expanded exponentially, growing larger and more grotesque with each passing second.
A crack appeared in the center of the pulsing mass, widening to reveal a cavernous mouth lined with razor-sharp teeth. The maw gaped wide and snapped shut with bone-crushing force, swallowing Doma whole in an instant.
The first blood of the final battle had been drawn.