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

Deep within an eerie, dimly lit fortress—a place that defied logic and seemed to twist and shift with every step—Muzan Kibutsuji sat on his ornate throne, fingers tapping against the armrest. His crimson eyes shimmered with irritation, his patience worn thin after centuries of disappointment from his subordinates.

A distorted ripple formed in the floor, and from the shadows emerged Akaza, kneeling before the Demon King. His usually calm and confident face was… unsettled.

Muzan's gaze bore into him. "You failed to eliminate Kamado Tanjiro. Again."

Akaza flinched. "It's not my fault, Master. Something… unexpected happened."

Muzan's fingers froze mid-tap. "Explain."

Akaza took a deep breath. "I located Tanjiro and his companions at a secluded hot spring. They were weak from training… it should have been easy. But then…"

Muzan's eyes narrowed. "Then what?"

"…A bald man appeared."

Silence. Muzan blinked. "A… bald man?"

Akaza's expression grew strained. "Yes. Completely hairless, wearing a towel, and… he punched the ground. The shockwave alone sent me flying into the forest."

Muzan's face twisted slightly. "A demon?"

Akaza shook his head violently. "No… I sensed no demonic aura. But his strength was… absurd. Unreal. Even for Upper Moons."

The room fell silent, except for the slow, rhythmic tap-tap-tap of Muzan's finger resuming its impatient beat.

"Describe him."

"Ordinary face. Completely blank expression. He introduced himself as… 'just a guy who's a hero for fun.'"

The other demons lurking in the shadows exchanged confused glances. Was this a joke?

Muzan's face darkened. "A human stronger than Upper Moons? Do you take me for a fool?"

Akaza bowed deeper, his forehead touching the floor. "I would never, Master. But I saw it with my own eyes. He treated me like a mosquito interrupting his bath."

The room's atmosphere grew heavy. Muzan's pride was wounded at the mere thought of a human possessing such power. "If this 'bald man' exists… you will investigate further. Find out his identity, his abilities, his weaknesses. If he interferes again—eliminate him."

"Yes, Master!" Akaza vanished into the shadows, leaving Muzan to stew in unsettling silence.

Muzan stared at his reflection in the dark floor, eyes narrowing. "A hairless threat…" he muttered.

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Meanwhile, Back at the Butterfly Mansion

Saitama was casually watering the plants in the garden, wearing a straw hat he found lying around.

"Sensei!" Tanjiro called, running up to him. "We need to continue training today."

Saitama gave him a thumbs up. "Sure. After lunch."

"Sensei, you know… you scared an Upper Moon last night," Zenitsu whispered, still in disbelief.

"Yeah? Which one?" Saitama asked, completely uninterested.

"Upper Moon Three! Akaza!"

"Oh." Saitama yawned. "Hope he's not mad about the bath thing."

The Hashira watching from the hallway could only sweatdrop. They were beginning to realize that this bald man might not just be a strong human… but something beyond comprehension.

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To Be Continued…

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