In the deepest part of the Infinity Castle, the walls shifted constantly, corridors folding and unfolding like a living puzzle. At the center of it all stood Muzan Kibutsuji, his pale fingers delicately holding a crystal orb. Through it, he had watched everything — the Lower Moon's pathetic attempt, Saitama's casual flick, and the absolute erasure that followed.
Silence stretched in the room.
None of the Upper Moons dared speak. Even Doma, who usually filled the air with his annoying chatter, stood perfectly still, his smile frozen into something that resembled fear.
Finally, Muzan's voice shattered the silence.
"He didn't even use a sword."
Kokushibo, the strongest of the Upper Moons, knelt, but his usually calm eyes were clouded with something rare — uncertainty. "Forgive me, Muzan-sama, but this… this is not something within the realm of humans or demons."
Muzan's fingers tightened around the orb, spiderweb cracks forming along its surface. "A human with such power? No breathing technique. No Nichirin Blade. No demon transformation. Just… punches?"
"Even Yoriichi, who came closest to killing you, relied on his blade and Sun Breathing," Akaza said quietly. "But this man…"
"This bald man," Doma added with a nervous laugh, though his usual playfulness was missing. "A shiny-headed threat, huh? Who would've thought?"
"Enough." Muzan's voice dripped with venom. "This isn't amusing. This is unacceptable."
The demons bowed lower.
Muzan's fury was not just because of the death of Lower Moon Four — Lower Moons were disposable — but because this anomaly was outside his calculations. Muzan prided himself on his control, his ability to predict, manipulate, and dominate every piece on the chessboard.
But this man had no scent of special lineage. No demonic aura. No celestial blessing. He was just a normal human.
A normal human who could end demons with a flick of his fingers.
"This… Saitama," Muzan spat the name like poison. "He must be eliminated before his very existence inspires hope in the Slayer Corps."
Kokushibo bowed lower. "Shall I go, Muzan-sama?"
"No." Muzan's smile was thin and cold. "Not yet. First, I want him tested by Upper Moon Six."
Gyutaro's grin split his face wide. "Ohhh, me and Daki? It's been a while since we fought someone fun!"
Daki, lounging lazily beside him, scoffed. "He's just a human. All these dramatic warnings are unnecessary."
"Then prove it." Muzan's eyes gleamed. "Kill him. And bring me his corpse."
The air in the room turned suffocating as Muzan's presence bore down on the demons. None dared question him, even if the dread in their hearts told them this bald man was anything but ordinary.
As the Infinity Castle twisted once more, sending Gyutaro and Daki hurtling toward the mortal realm, Kokushibo stayed silent. His fingers twitched at his side, as if remembering an ancient fear — a fear that only one man had ever caused him.
Yoriichi… no, this feels different.
This is not a swordsman. This is a storm wearing human skin.
---
Meanwhile, back at the Slayer Corps estate, Saitama was hanging up laundry.
"Why is this estate so big?" he muttered, pinning a sleeve to the line. "Do they really need this many uniforms?"
"Ah, Saitama-san!" Tanjiro called, jogging up to him. "There's been a report — two powerful demons were seen approaching the estate!"
"Oh?" Saitama raised a brow. "Finally. I was starting to get bored."
"Please be careful!" Tanjiro bowed. "They're Upper Moons — incredibly dangerous!"
"Cool," Saitama said, utterly unbothered. "I'll be there in a sec. Just need to finish the laundry."
"…You're doing laundry?"
"Yeah, Genos usually does it, but he's not here, so someone has to."
Tanjiro stared, half in admiration, half in confusion. "You're… surprisingly humble."
Saitama shrugged. "I'm not humble. I just don't have much to do until they show up."
At that exact moment, the sky darkened unnaturally, and a sickly, corrupted mist began to roll in from the forest. The air itself seemed to tremble as Gyutaro's voice rang out.
"Ooooooi! Demon Slayer Corps! Time to die, you weaklings!"
Saitama sighed, tossing aside the basket of clothes. "Alright, finally."
As he walked toward the gate, Tanjiro, Zenitsu, and Inosuke rushed after him, swords drawn.
"Upper Moons are on a whole different level!" Zenitsu was already shaking. "Saitama-san, you should leave this to us!"
Saitama glanced at them, scratching his cheek. "Nah, I got this."
"But—!"
Before they could argue further, Saitama opened the gate, stepping into the mist. Gyutaro and Daki stood there, radiating malicious energy, their eyes glowing bright as blood moons.
"You the bald freak everyone's talking about?" Gyutaro sneered.
Saitama looked them over.
"One's moldy, the other's annoying."
He cracked his knuckles.
"Let's get this over with."
The fight had begun — though for Saitama, it was probably just a warm-up.
---
End of Chapter 35