The sky above the Demon Slayer Corps' headquarters was no longer calm. The crack in reality had stretched into a gaping wound, and out of it spilled a sinister, inky mist, curling down toward the earth like hungry fingers. The Hashira stood frozen, weapons drawn, unsure whether to prepare for battle — or run.
"What… is that?" Mitsuri whispered, her voice trembling slightly.
Even Saitama, who usually treated every threat with the same half-hearted boredom, was paying attention now. His gaze locked onto the center of the crack, where a shape was emerging — a massive figure, far larger than anything they'd faced before.
Genos' sensors were already blaring warnings.
"Sensei, this being's energy signature is unstable. It's not from this dimension at all."
"Figured." Saitama cracked his neck. "Finally, something interesting."
---
From the Rift, A Forgotten Demon Lord
The shape fully emerged — a monstrous figure covered in scales like polished obsidian, with six jagged horns sprouting from its skull and six arms, each one clutching a different type of weapon. Its eyes burned like molten gold, filled with both rage and madness.
"You. Freed. Me." the creature's voice rippled across the air, vibrating deep in everyone's bones.
The Hashira staggered back, even the air around them growing heavy with malice.
"Who are you?" Giyuu demanded, sword at the ready.
The creature's grin was wide and jagged. "I am Azrathol, the Demon King before Muzan. I ruled this world before you insects sealed me beyond the veil!"
"Before Muzan?" Shinobu's eyes widened in disbelief. "That's impossible! Muzan was the first demon!"
"No," Azrathol growled. "Muzan was a weakling… a coward who inherited scraps of my power after your ancestors betrayed me."
---
A Rift Between Realities
The presence of Azrathol was not just a threat to this world — his very existence was tearing apart the thin walls between dimensions. Saitama and Genos both felt it — the familiar hum of their own universe's energy leaking through the cracks.
"Sensei," Genos said, "if this goes on, it won't just be demons — all sorts of beings from different worlds could pour in."
Saitama scratched his cheek. "Sounds annoying."
Azrathol's attention finally fell on Saitama. "And you. You are not of this world. You carry the scent of countless battles… but no aura of fear. Why?"
Saitama just shrugged. "Dunno. Haven't felt scared in a long time. You some kind of big boss?"
Azrathol's grin widened, jagged teeth gleaming. "I will devour you first, outsider."
---
The Hashira's Decision
Rengoku stepped forward, flames dancing along his blade. "Whether you are from this world or another, you threaten humanity — and we shall stop you!"
The Hashira stood in a line, swords raised, determination burning in their eyes. Even Zenitsu, trembling as always, found his grip firm.
But Azrathol only laughed. "You think your little blades can harm me? I was a god before your ancestors stole my throne!"
Saitama stretched his arms lazily. "Wanna spar?"
The Hashira nearly fell over.
"Saitama-dono, this is serious!" Shinobu scolded.
"It's fine, it's fine." Saitama stepped forward, looking up at the towering demon king. "You look strong. But let's find out."
---
Saitama vs Azrathol - The First Clash
Azrathol swung one of his massive blades, aiming to cleave Saitama in half. The shockwave alone uprooted trees and cracked the ground. The Hashira braced themselves — but Saitama didn't move until the last second.
Tap.
With a casual flick of his finger, Saitama redirected the blade's force straight into the ground, splitting the earth open in a hundred-meter trench.
Azrathol's smile faltered for the first time.
"What…?"
Saitama clenched his fist. "Okay. My turn."
BOOM.
He launched forward, his punch connecting with Azrathol's chest. The air itself exploded outward, flattening the entire forest behind them.
Azrathol was sent flying through a mountain.
The Hashira stood speechless.
"Y-y-you just sent him through a whole mountain!" Inosuke screamed. "That's cheating!"
Saitama shrugged. "Thought he could take it."
---
But Azrathol Wasn't Done
From the rubble, Azrathol emerged, his form already regenerating — but slower than expected. His expression was a mix of fury and… something else.
Fear.
"You…" Azrathol's voice was unsteady. "What are you?"
Saitama just scratched his head. "I'm a hero for fun."
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End of Chapter 48
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