Execution

The air inside the crumbling hall was oppressive, thick with the metallic scent of blood and the suffocating weight of Kokushibo's demonic aura. The once-pristine Infinity Castle was reduced to jagged rubble, its eerie beauty marred by the relentless onslaught of the battle. Kokushibo stood, his grotesque, monstrous form heaving with exertion. His six maddened eyes darted across the room, searching desperately for an opening, a weakness in the human before him.

Bell stood calmly in the center of the devastation, his katana resting loosely at his side. His posture was almost casual, but his gaze was sharp, unwavering. His once-smirking expression had shifted into one of mild disappointment, as though he were a teacher observing a student's failed attempt at a lesson.

"You've grown desperate, Kokushibo," Bell said evenly, his voice cutting through the chaos. "But desperation without control is useless."

Kokushibo let out a guttural roar, his scorpion-like appendages thrashing wildly around him, carving deep gouges into the floor and walls. "Do not patronize me, mortal!" he bellowed, his distorted voice reverberating like a storm. "I am the pinnacle of strength! You are nothing but an arrogant fool!"

With a burst of speed, Kokushibo lunged at Bell, his monstrous form a whirlwind of blades and stingers. His katana, pulsating with malevolent energy, came down in a devastating arc aimed directly at Bell's head. But Bell was gone before the strike landed, his figure dissolving into a blur of movement.

Reappearing behind Kokushibo, Bell whispered almost mockingly, "Too slow."

The demon whirled around, his scorpion appendages lashing out in every direction, but Bell danced between them with infuriating ease. His katana flashed in the dim light, severing two of the appendages in a single, fluid motion. Black blood sprayed across the rubble, but Kokushibo barely flinched, his regeneration kicking in almost immediately.

"You're still holding back!" Kokushibo roared, his six eyes blazing with fury. "Why?! Fight me with everything you have!"

Bell tilted his head, a faint smirk returning to his lips. "Why should I?" he asked, his tone almost bored. "You're not even close to pushing me. This isn't a fight—it's a demonstration."

The words cut deeper than any blade, igniting a new wave of rage in Kokushibo. With a roar, he unleashed a torrent of crescent-shaped slashes, the destructive waves tearing through the already ruined hall. Bell countered with a single, precise slash of his own, the force of his strike nullifying Kokushibo's attack and sending a shockwave rippling outward.

Kokushibo staggered, his monstrous form trembling as he struggled to keep up with Bell's relentless assault. His once-imposing presence was now marred by desperation and exhaustion. The thin tubes protruding from his body hissed and sputtered, leaking steam as his regeneration faltered under the strain.

Bell stepped closer, his katana glinting ominously in the dim light. "You've reached your limit," he said softly, his tone almost pitying. "This is the best you can do, isn't it?"

"No!" Kokushibo snarled, his six eyes narrowing. "I am stronger! I am invincible!"

Bell sighed, shaking his head. "Strength without control is nothing. Invincibility without purpose is meaningless. You've spent centuries chasing power, and yet you still don't understand that."

Kokushibo roared in defiance, his monstrous form lurching forward for one final, desperate attack. His katana came down with all the force he could muster, the ground beneath him shattering under the weight of his strike.

But Bell was faster. His katana moved in a blur, intercepting Kokushibo's blade and shattering it with a resounding crack. Before the demon could react, Bell's katana slashed upward, severing Kokushibo's arm at the shoulder. Another strike followed, then another, each one precise and devastating.

Kokushibo fell to his knees, his monstrous form trembling as his regeneration failed to keep up with the damage. His six eyes stared up at Bell, a mixture of rage, disbelief, and fear flickering within them.

"You... you cannot defeat me," he rasped, his voice weak and trembling. "I am... eternal."

Bell stepped closer, his katana poised for the final strike. "Eternal?" he repeated, his voice quiet but firm. "No. You're just another stepping stone."

With a single, decisive slash, Bell's katana cleaved through Kokushibo's neck, severing his head from his body. The demon's monstrous form convulsed violently before collapsing into a heap. The black and red appendages writhed for a moment before falling still.

For a brief moment, the hall was silent, save for the faint hiss of steam escaping from Kokushibo's lifeless body. Bell stood over the fallen demon, his katana glinting in the dim light, his expression calm and unreadable.

Bell sheathed his katana, turning away from Kokushibo's remains. He glanced around the ruined hall, his gaze lingering on the destruction for a moment before settling on the far end of the room.

"Muzan," he murmured to himself, a faint smile tugging at the corner of his lips. "I hope you've been paying attention."

As he stepped forward, the air grew colder, heavier, as though the castle itself was reacting to Kokushibo's death. The shadows deepened, and a sense of foreboding settled over the battlefield. But Bell's expression remained unshaken, his determination burning brighter than ever.

The end was near, and Bell was ready.

AN: On my Patreon, this arc and Demon Slayer is finished so check it out: pat/reon.com/Wrizz1 (jus remove the slash between pat and reon)

I would also like to ask of you to start suggesting worlds where Bell could go to next, just comment them, okay?