Infinity Castle
Having just finished with Kokushibo, Kaito cast his divine sense across the entire Infinity Castle. He swept through it once, confirmed that none of the Corps members were in any real danger, and stopped paying attention to them.
"There he is."
Through his divine sense, he had found Kibutsuji Muzan's location. Every remaining member of the Twelve Kizuki was clustered around him.
'So killing Kokushibo was enough to spook him. Good.'
The moment Kaito had cut Kokushibo down, Muzan had felt it. Gripped by the terror of death, he had immediately called back every member of the Twelve Kizuki, pulling them all to his side.
Hantengu, Upper Rank Four, knelt on the ground and looked up at Muzan uneasily.
"Muzan-sama, why have you recalled all of us? The Demon Slayer Corps has already broken inside!"
"Kokushibo is dead. One move."
Muzan's voice was flat. His blood-red eyes moved slowly over the row of kneeling demons.
Daki went rigid beside Gyutaro.
"One move?! Muzan-sama, is this person even from the Demon Slayer Corps?"
As Upper Rank demons, they understood what that meant better than anyone. Even within the Twelve Kizuki, the distance between them and Kokushibo was vast. Kokushibo alone could have wiped out every other member without breaking a sweat.
The image of Kokushibo's death had already twisted Muzan's expression into something ugly. A flash of killing intent moved through his eyes.
"Useless. All of you, useless. Can't you even stop one person?!"
He was performing the scumbag boss playbook to perfection; blame the subordinates, never once consider that the problem might be staring back at you from the mirror.
The Twelve Kizuki pressed their heads lower and said nothing. They all knew that Muzan in this state might kill them just to feel better about it.
"Oh my. Calling your own people useless. Muzan-sama must be feeling very brave today."
Every head in the room snapped up.
"Who said that?! Who dares?!"
Kibutsuji Muzan was no longer paying any attention to the demons at his feet. His blood-red eyes had locked onto the young man standing across from him. The one who had killed Doma. The one who had killed Kokushibo.
"You. Why are you still coming? You think you can actually kill me?"
"Only one way to find out."
Kaito was done talking. He channelled spiritual energy into a golden chain and flung it straight at Muzan.
Muzan saw it coming. He grabbed Hantengu in front of him and shoved him into the path of it. The golden chain coiled around Hantengu and locked tight.
"Muzan-sama! Save me!!"
Muzan was already running.
"Hold him off! All of you! If he gets through, you all die!!!"
The demons scrambled to their feet. Before any of them could move, a voice dropped over the room like a falling ceiling.
"Kneel. Who told you to stand?"
Kaito's aura detonated outward. The air itself buckled. Every demon that had begun to rise crumpled straight back to their knees, pinned by a pressure that seemed to come from every direction at once.
"I can't move…"
"How is this…"
The golden chain drew slowly, steadily tighter. Hantengu's face went from red to purple, his throat working for a sound that would never come.
"Bang!"
Watching Hantengu get crushed, Kibutsuji Muzan felt a fear he had never felt before settle into his bones. One second slower, and that would have been him.
"Scapegoat won't save you. Where are you running?"
Muzan's mind went straight to self-destruction. It was the only exit he had left.
He never got the chance. Under Kaito's divine sense, every movement he made was perfectly visible. Not chaining him earlier had been deliberate, Kaito had simply been playing with him.
"What?! When did — how?!"
The golden chain was already around him.
Muzan stared at it. He had just seen it, still far away.
How?
"Nothing's impossible. Here's some advice: if you want to be a villain, practice more."
Kaito pulled the chain, dragged Muzan in front of him, and looked back at the remaining demons.
"Got your boss. As for you guys, Tenkuu, finish them."
Tenkuu launched from his side without hesitation. Under the terrified stares of the remaining demons, she moved through them one by one. The Twelve Kizuki were no more. With Nakime's death, the Infinity Castle began to crack and collapse around them.
"We're outside!"
The Demon Slayer Corps members found themselves back on the surface under a full moon. Whatever had happened in there, Kaito had done it.
"Whoosh!"
"Kaito-sama!"
Everyone pressed forward as Kaito appeared before them, Kibutsuji Muzan in tow. Rengoku Kyojuro's eyes landed immediately on the bound figure beside him.
"Kaito-sama, who is that?"
"Guess."
Rengoku Kyojuro looked at the figure carefully, and then the thought came to him, quiet and almost unbelievable.
"This… could this be… Kibutsuji Muzan?"
"Got it. No prize though."
For a moment, no one moved. Then the crowd erupted.
"That's Muzan?! Kibutsuji Muzan?!"
"He's right here, bound, right in front of us?!"
There was no holding anyone back after that. They surged forward, years of grief and fury finally finding somewhere to go.
"Muzan, die for what you did to my family!!!"
"Give me back my mother!!!"
"I want you dead!!!"
Bound by the golden chain, Kibutsuji Muzan could only endure it — the nichirin blades, the fists, the weight of hundreds of people's hatred crashing into him again and again.
Kaito watched in silence. Muzan had spent his entire existence leaving behind nothing but ruin and grief. This was exactly what he deserved.
Time passed. Even with his regeneration suppressed, Muzan was ground down to the very edge of death. Kaito looked at him, then looked up at the ridge, where the sky had begun to soften and thin.
"Everyone. It's over."
The first light of the sun broke across the earth. Kibutsuji Muzan let out one final scream and crumbled into ash.
"Yeah!!!"
"It's finally over!!!"
"Mother… sister… I did it…"
"Michiko… you can rest now…"
Corps members dropped to their knees across the hillside, weeping openly. Kanae Kocho, standing quietly beside Kaito, reached over and gently took his left hand. Her eyes rested on his face, warm and unhurried.
"All of this was because of you, Kaito-sama. Meeting you is the greatest fortune of my life."
She rose onto her tiptoes and pressed a light kiss to his cheek.
Kaito turned. Without a moment's hesitation, he pulled her into his arms and leaned close to her ear.
"You made the first move, you know."