The One Punch Man (a.k.a Saitama) in Demon Slayer

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Lost in the Maze

The Hashira stood frozen, their eyes scanning the shifting walls of The Black Labyrinth.

Endless black corridors stretched before them, twisting and bending in ways that defied reality. The sky was gone. The ground no longer felt solid. It was as if they were trapped in an illusion made real.

Giyu tightened his grip on his sword. "This is not just some demon's blood art… this is something else entirely."

Shinobu nodded. "Yes. It feels like we've been… pulled into another realm."

"Not just any realm," Muichiro murmured, his voice eerily calm. "We're inside his domain."

Tenma's voice echoed through the darkness.

"You are beginning to understand. Good. But knowledge won't save you here. You see—in my domain, your senses betray you."

Suddenly—slashes came from nowhere.

Sching! Sching! Sching!

Tengen barely dodged as invisible blades cut through the air. "Tch—what the hell?!"

Obanai blocked just in time, but his haori was sliced cleanly in half. "I didn't even see the attack coming."

Shinobu's eyes widened. "He's right. Our senses are being distorted. We won't even see our own deaths coming…"

"Then we must rely on instinct!" Rengoku shouted, flames roaring around him as he charged forward.

BOOM!

His sword clashed against an unseen force, sparks flying as the heat from his blade illuminated a faint silhouette of something enormous.

The darkness twisted.

And then—it struck back.

A massive shadowy claw smashed into Rengoku's side, sending him crashing into a pillar.

"Rengoku!" Tengen yelled, leaping forward to catch him.

But before he could move—another slash came out of nowhere.

Saitama blocked it with one finger.

"Man, this place is really annoying," he muttered, glancing at the unseen force that had tried to cut him. "I can't even tell where I'm supposed to punch."

Tenma's laughter echoed. "And that is precisely why you will lose."

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The Monster in the Maze

The darkness shifted again, forming a towering figure in front of them.

It was no longer just Tenma.

A monstrous being emerged from the void—its body made entirely of shifting shadows, its face featureless except for two glowing white eyes. It had no physical form, yet its attacks were real.

Shinobu narrowed her eyes. "A creature that exists only in darkness… how do we even fight something like that?"

Tengen smirked. "Simple. We destroy the entire maze."

BOOM!

Without hesitation, he swung his blades, explosions erupting along the walls of the labyrinth. The black stone cracked and crumbled—but the maze instantly reformed.

Tenma laughed again. "Ah… an amusing attempt. But here, destruction is meaningless."

Obanai gritted his teeth. "Then what do you suggest? Fighting an enemy we can't see?"

"I have a different idea," Muichiro said calmly.

He closed his eyes—and stopped breathing.

Everyone turned to look at him in shock.

"Oi, kid—this isn't the time to be passing out," Tengen called.

But then—Muichiro vanished.

No sound. No movement. No presence.

And in that moment—the darkness hesitated.

Giyu's eyes widened. "He's… not being detected?"

Shinobu realized it immediately. "I see. The enemy is tracking us through our presence. But if we erase it completely…"

Muichiro reappeared behind Tenma's monstrous form, sword already mid-swing.

"Mist Breathing, Seventh Form—Obscuring Clouds!"

SLASH!

The blade sliced through the darkness.

For the first time—Tenma screamed.

The shadows trembled, recoiling like a wounded beast.

Rengoku grinned. "So that's the trick! We need to attack while hidden!"

Giyu nodded. "Then let's use that to our advantage."

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The Unstoppable Hero

While the Hashira figured out how to fight, Saitama yawned.

"Yeah, yeah, all that's cool, but I still don't know where to punch."

Tenma growled. "You… You mock me even now?"

The shadows lashed toward him, forming dozens of massive blades.

SLASH!

The attacks struck Saitama directly.

A wave of silence passed through the battlefield.

And then—Saitama scratched his head.

"Huh. That kinda tickled."

Tenma froze.

Tengen whistled. "Man, you're just built different, huh?"

Saitama sighed. "Alright, I'm tired of this game."

And then—he punched.

BOOM!

The shockwave ripped through the labyrinth, shattering every shadow in its path. The once-invincible maze collapsed as Tenma's form began to break apart.

The Hashira could see the sky again.

Rengoku grinned. "That's more like it!"

Tenma, now injured for the first time in centuries, glared at Saitama with pure hatred. "You… You are not human."

Saitama cracked his knuckles.

"Yeah? Well, you're not much of a final boss either."

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To Be Continued…

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Chapter Highlights:

Tenma's Black Labyrinth forces the Hashira to fight without their senses.

A new monster of shadows emerges, acting as Tenma's ultimate guardian.

Muichiro figures out how to counter the unseen attacks by erasing his presence.

Saitama ignores everything and simply destroys the entire maze.

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