Chapter 83: the Final Dance of the Moon!
Enjoy~~~
In another corner of the Infinity Castle, a horrifying battlefield stood drenched in the smell of blood and iron.
The Upper Moon One, "Kokushibo," stood alone with his overwhelming presence and terrifying flesh swords against three fighters who had surpassed all description.
They were not merely "Hashira" anymore… they had long transcended that level of power. They were users of the Mark at its fullest brilliance, warriors who had gone through countless bloody battles, and whose goals had united into a single cutting blade.
And what about three Mark users burning away their lives with "forbidden" breathing techniques, turning every simple movement into a desperate, ultimate attack beyond reason?
And yet…
"Even with all this… you still cannot defeat me," Kokushibo said in a cold, majestic voice heavy with centuries of bloodshed.
The First Moon spoke as he wiped blood from his cheek with his thumb:
"I am Upper Moon One. The strongest demon after Kibutsuji Muzan-sama. I shall acknowledge you as some of the strongest opponents I have fought in my long life… I lived for centuries, wandering throughout Japan for decades seeking the strong. I never once stopped training, sharpening my craft, and increasing my power. So… be proud that you will die in this battle."
Kokushibo looked coldly at the three before him. Despite their fatal wounds and constant bleeding, they stood with the same determination—no, even greater determination. Their eyes held no fear, focused only on fighting until their final breath.
"Don't look at us like that, old man, as if you're invincible! Or did you already forget who blew off half your head earlier?"
Hakuji smiled mockingly while raising his fist covered by a gauntlet reinforced with Nichirin metal stained in blood… Kokushibo's blood.
Kokushibo narrowed all six of his eyes slightly in irritation.
"Akaza… or rather, Hakuji. It seems you became even more arrogant and talkative after returning to being a weak human… Have you spent your recent time training your tongue instead of refining your martial arts? Unfortunately…"
Kokushibo raised his strange eye-covered sword and vanished like a phantom.
In the next moment, he and Hakuji clashed violently in midair, sending a shockwave that shattered the ground beneath them.
"Unfortunately, Hakuji… a true Demon Slayer kills demons with the sword, and it seems you still do not understand the noble art of swordsmanship…" Kokushibo whispered while pressing his blade against Hakuji's gauntlets, sparks exploding everywhere. "You are merely a fool swinging his fists like a wild beast. I did not hate your fighting style when you were a demon. I respected it as a different martial art… But seeing its weakness and fragility now, how pitiful."
"Shut your mouth, you arrogant bastard! Crushing you with these 'weak' fists will be the greatest humiliation of your death!"
Hakuji roared. In the next instant, he blocked Kokushibo's attack with the short sword Rin had given him, then kicked Kokushibo hard in the chest.
Hakuji immediately returned the short blade to its sheath skillfully and assumed his battle stance using Bojutsu, while Kokushibo landed calmly on the ground without being greatly affected by the kick.
In the back, Zenichiro and Tokito were heavily injured and exhausted to the point they could barely move quickly anymore. Their breathing was ragged, their muscles screaming in agony.
So they used Hakuji's reckless clash to gain a few seconds to recover and stabilize their breathing. In the end, their primary goal was not to kill Kokushibo—because they fully understood how impossible that was—but rather to "prevent" him from moving freely throughout the castle and interfering in the other Hashira battles to slaughter them. They were acting as a human shield.
Then… every fighter suddenly froze.
Hakuji and Kokushibo both raised their heads simultaneously toward the left wall.
The sound of terrifying consecutive explosions… collapsing walls… screams… and an overwhelming pressure approaching rapidly!
"What are these explosions…? Is this one of the demons' techniques? It's approaching insanely fast!" Tokito muttered with difficulty.
"No… this is a Hashira…" Kokushibo muttered with a frown, his six eyes narrowing almost completely shut.
Hearing that, Hakuji frowned and cursed himself. Ever since becoming human again, he had lost his previous demon techniques (Compass Needle) and his overwhelming perception, causing him to recognize the approaching aura later than Kokushibo.
"No… wait, this isn't just a Hashira… a demon? That feeling… that aura… it's demonic!" Hakuji thought in shock.
Everyone watched nervously. As the sound drew closer and louder, everyone unconsciously held their breath.
And then…
BOOOOOOM!
A massive explosion erupted, shattering a huge section of the thick wall. From the dust and rubble emerged a figure carrying an overwhelming aura… half demon, half Hashira!
"Rin-sama!" Zenichiro shouted in shock and joy.
Meanwhile, Tokito instinctively assumed a guarded stance despite his pain… because the person before him—with white hair, crimson eyes, and black tendrils—looked undeniably like a demon. Not just any demon either… his aura and killing intent were denser and more terrifying than even Kokushibo's, perhaps even Muzan's himself!
"Zenichiro-senpai, Tokito-kun, Hakuji-san… are you alright?"
A familiar voice echoed out. Everyone turned to see Tanjiro landing gently on the ground after Rin released his waist. Tanjiro looked at them with deep concern and hope in his eyes.
Rin did not speak. His crimson eyes, in the Demon King state, were focused solely on Kokushibo.
Looking at the First Moon, Rin appeared calm and icy on the outside, but internally he was drowning in indescribable chaos and turmoil.
After all… in another timeline, in another life… this demon, Michikatsu, had once been his older brother. Seeing that face—even twisted by six eyes—immediately reminded him of the human Michikatsu, with all his warmth and coldness alike.
"So… you have finally arrived, Yukihara Rin."
Kokushibo spoke with deadly calmness while resting his sword on his shoulder, all six eyes focused solely and exclusively on Rin, completely ignoring everyone else.
"It seems you found a solution to your suicidal technique and decided to become a monster to defeat monsters."
Rin did not answer. Instead, he slowly turned and addressed the person hiding in the shadows behind him.
"Yushiro… take Nakime and Daki's head. The others will protect you until you finish."
At that moment, Yushiro, Lady Tamayo's subordinate, emerged from the shadows carrying Nakime's unconscious, mangled body over his shoulder. He looked at Rin with the same complicated expression as before—a mixture of fear, respect, and confusion toward this boy who surpassed demons themselves.
(After killing Ryoga, Rin headed toward Muzan, but then sensed Kokushibo nearby. Seeing only three fighters battling him, he couldn't stop himself from changing course to save them and finish off Upper Moon One. On the way, he found Yushiro alone. Yushiro explained that he and Lady Tamayo had suddenly been dragged into the castle from their hiding place, and they separated under Tamayo's orders—she would search for Muzan to begin her plan, while Yushiro would execute Rin's plan to capture Nakime. So Rin brought him along.)
At this moment, Rin silently analyzed the situation:
"What exactly is Muzan planning? The demons and Upper Moons are much stronger than expected, yet Muzan himself still hasn't appeared. Is he trying to isolate and eliminate the Hashira one by one? Or…"
Rin frowned.
Tanjiro and Yushiro jumped toward Zenichiro, Tokito, and Hakuji, forming a defensive formation.
Tanjiro carried Daki's still-living head—which continued cursing nonstop—while Yushiro placed Nakime's body on the ground and immediately began using his talismans and papers to control her mind and connect his consciousness to the castle.
"I'll need some time… The castle is enormous, and Muzan and Nakime's mental resistance is strong. I need time to move all of us back to the surface," Yushiro said while biting his thumb and drawing symbols with blood.
"Mm… take your time," Rin nodded without turning around.
"Perhaps…" Rin thought, "Muzan already realized I'm extremely dangerous and a genuine threat. So maybe he's hiding now, analyzing my fighting style through the Upper Moons' eyes and searching for a way to counter my techniques before the final battle. Meanwhile, he's using lower-ranked demons to keep every other fighter occupied and prevent them from joining."
"Good… that's exactly what I want. I only hope he doesn't have some idiotic escape plan prepared like usual."
With a light leap, Rin landed quietly beside Hakuji. He began walking forward, and as he passed him, he gently patted Hakuji's shoulder and spoke warmly despite his terrifying appearance:
"You did an incredible job, Hakuji… thank you."
"Hmph…" Hakuji turned his face away to hide a small smile and said coldly, "You can thank me better by crushing that six-eyed spider over there."
He said that while limping toward the others. Hakuji was severely injured, his human body bleeding from numerous places. Fighting as a human was never easy; wounds did not regenerate, and broken bones hurt like hell.
His only saving grace was that Rin's hellish training and torture in the past had made him accustomed to fatal pain and fighting while critically injured.
Rin took two steps forward and raised his eyes toward the First Moon.
"Kokushibo…" Rin suddenly asked in a calm voice carrying hidden sorrow, "Why did you become a demon?"
That question made Kokushibo frown intensely, his grip tightening on his sword. He simply chose to ignore it and launched toward Rin at supersonic speed, raising his blade to cut down this insolent brat who dared ask about his shameful past.
"I'll tell you… if you survive long enough to hear it!"
Looking at Kokushibo charging him, Rin sighed. He closed his crimson eyes, and his terrifying appearance began to change.
The tendrils shrank. The white hair disappeared. The demonic aura of the Muzan Template faded, returning him to his human appearance… but with fundamental differences.
[Special Skill: Template Gears — Tsugikuni Yoriichi Template… Activated!]
Kokushibo froze mid-attack.
All six of his eyes widened in shock that completely paralyzed his thoughts.
Rin blocked Kokushibo's terrifying strike… with an ordinary sword, using a simple, smooth, impossibly calm motion… exactly like nature itself.
Rin's demonic appearance vanished entirely. His hair became short black hair tipped with crimson flames, and his eyes turned dark red—the color of Yoriichi's eyes. On his forehead, the original Demon Slayer Mark glowed brightly, the very mark once carried by the strongest human in history.
His appearance, his stance, the peaceful aura like a warm sun, and the way he held his sword…
It reminded Kokushibo of his younger brother Yoriichi so terrifyingly that Kokushibo unconsciously stepped back and muttered in a trembling voice:
"…Yoriichi?!"
"It is tragic… seeing you like this, older brother…"
Rin spoke calmly, carrying deep sorrow.
As he said those words, his human heart began beating again, and the demonic coldness surrounding his soul faded. Looking at "Michikatsu," this timeline's Kokushibo, Rin—or rather the remnants of Yoriichi's soul inside him—hesitated briefly.
But remembering all of Kokushibo's monstrous actions through the centuries, his betrayal of the Demon Slayer Corps, and the countless innocents he devoured… this had to end.
"Perhaps he isn't truly my brother in this timeline…" Rin thought sadly. "But killing him will still be difficult. I'm sorry, brother… but…"
Rin remembered his mother Yomi's exhausted, gentle face, his father whom he had just killed, and his little sister Eiri clinging tightly to his back.
Rin placed his left hand gently behind him and touched Eiri's head. Using cursed energy—with Rina helping control it precisely—he strengthened the protection around Eiri's body so she wouldn't be harmed by the upcoming speed.
"You… YOOORIIICHI!!"
The moment Rin called him "older brother," Kokushibo's mind erupted into madness!
A horrifying impossible thought entered his head: Yoriichi had returned to life inside this child's body just to mock him!
Kokushibo remembered that cursed night… how his younger brother had died standing from old age, not beneath his sword as Kokushibo had desperately wished. Yoriichi died undefeated, like a ruler beyond reach.
Kokushibo's hatred and rage exploded as he attacked with his absolute full power, unleashing Moon Breathing techniques that tore through space itself.
"Moon Breathing — Sixteenth Form: Moonbow, Half Moon!"
But Rin…
With absolute simplicity, and without any expression other than a single tear falling from his eye…
Vanished.
He passed through all those lunar blades as though they were illusions and appeared slowly behind Kokushibo… like a ghost.
In the next moment…
Kokushibo froze.
Everything stopped.
The First Moon's head slowly slid from his neck.
As Kokushibo watched his decapitated body collapse through the air before him, his face filled with shock, emptiness, and utter incomprehension.
Looking at Rin's back as he walked away, Kokushibo felt as if he were staring once more at his younger brother's back… that broad back he could never catch up to. The back he could never stand before as a dependable older brother.
He had always been far weaker than his younger brother… the younger brother who never understood the true value of his own power, the very power Kokushibo sacrificed his soul and humanity for.
"I created this form… solely for this day. For you…"
Rin said softly without turning around.
"Michikatsu-niichan was a genius, and I knew you would eventually overcome a demon's weakness of neck decapitation and regenerate your head mid-battle. So… I had to create a strike that would not allow regeneration."
"Moon Breathing — Secret Form: Michikatsu."
This was a secret form Rin created using the memories of "Tsugikuni Rin" from the alternate timeline and the memories he shared with Yoriichi and Michikatsu.
This was not merely the ultimate breathing technique…
It was the embodiment of Moon Breathing itself, combined with Sun energy and cursed energy to completely disable demonic regeneration.
"I'm sorry, older brother… but it's finally time for your rest."
Rin turned around, his sorrowful tearful eyes looking toward Kokushibo.
Hearing those words, Kokushibo showed no anger this time. Instead, he noticed Rin's body trembling violently. That special technique had placed monstrous strain upon the boy's muscles.
"Moon Breathing…" Kokushibo thought in disbelief. "Did Yoriichi learn my Moon Breathing? No… he even created a technique more beautiful and powerful than anything I developed over centuries?"
In those final moments of existence, while his body crumbled into ash, Kokushibo finally understood the bitter truth he had fled from for centuries:
He never truly wanted to become the strongest.
He never wanted immortality.
He only wanted… to become like Yoriichi. To stand beside him equally… as a true older brother someone could rely on.
Kokushibo slowly closed all six eyes, abandoning any attempt to regenerate his head and finally accepting his end.
His final thought before vanishing completely was:
"I'm sorry, Yoriichi… I should never have broken that little flute…"
The words escaped his lips as the faintest whisper before he became ash.
Seeing the hatred gone from Kokushibo's face at last, Rin bit his lip until it bled, then released a sigh burdened with centuries of sorrow.
Still wearing that mournful expression, Rin returned to his normal human appearance and walked with exhausted steps toward Tokito and the others, who stared at him silently with awe and reverence.
"Rest in peace… oniisan."
Rin whispered to the ashes.
And in that moment, Rin himself did not know whether he spoke as "Tsugikuni Rin," as "Yukihara Rin," or even as "Yoriichi," because the template's influence and memories had fused into his soul forever.
It was simply… the tragic end of two brothers separated by envy and reunited by death.
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I love the brothers Yoriichi and Michikatsu… I hope I didn't ruin them.
If you enjoyed the chapter, please tell me your thoughts in the comments. That's my only motivation to continue 😇❤️