Even Muzan's analytical mind capable of processing multiple thoughts simultaneously could not immediately interpret Kokushibo's metaphor.
The phrase "destroying someone by breaking their spirit" lingered in his mind without clear meaning.
Rui, standing nearby, froze completely when he saw Kokushibo casually resting an arm on Muzan's shoulder.
That level of familiarity between Upper Rank One and their master was something he had never imagined witnessing.
Even among demons, hierarchy was absolute but here, it seemed… strangely relaxed.
Rui lowered his head immediately.
He did not dare speak.
Muzan's gaze shifted toward him briefly.
For a moment, an instinctive discomfort arose not shame, but a desire to avoid unnecessary perception.
"Nakime," Muzan said calmly, "take Rui elsewhere."
A biwa tone echoed softly through the Infinity Castle.
Space folded.
Rui vanished alongside Nakime.
They reappeared in a quieter section of the Infinity Castle, resembling a dimly lit annex connected to Nakime's Blood Demon Art.
Rui looked around cautiously.
"Where is this…?"
Nakime adjusted her biwa slightly.
"This is one of the castle's annex rooms. You will remain here for now."
Rui nodded slowly, still obedient.
As he stepped forward, he nearly stepped on scattered papers across the floor.
"Stop."
Both Nakime and a nearby figure spoke at once.
Rui froze instantly.
A demon with drums embedded in his body sat nearby Kyogai carefully writing manuscripts with unusual focus.
Nakime's expression remained composed as she knelt and reorganized the scattered pages with precision.
"Do not disturb his work," she said flatly.
Kyogai continued writing without looking up.
"I've reached the bathroom chapter already."
Nakime nodded once in approval.
"Good progress."
She then handed Rui a set of papers.
"Lord Muzan and Lord Kokushibo are discussing important matters. Stay here and read."
Rui accepted them silently.
He did not yet understand what kind of "important matter" this would become.
Meanwhile, in another part of the Infinity Castle, Muzan sat with Kokushibo in a formal chamber.
Kokushibo's presence remained calm, composed yet suffocatingly dominant.
Muzan's attention returned to the earlier statement.
"Explain it clearly," Muzan said. "What does it mean to destroy someone's spirit instead of killing them?"
Kokushibo did not answer immediately.
Instead, he studied Muzan for a moment, as if deciding how much truth to reveal.
Then he spoke.
"It means breaking their conviction without breaking their body."
Muzan narrowed his eyes.
Kokushibo continued.
"A corpse is harmless. A broken will is obedient."
Muzan leaned slightly forward.
"Go on."
Kokushibo's tone remained steady.
"That boy Kamado Tanjiro does not yet understand the nature of demons."
"He believes conviction alone defines justice."
Muzan's expression shifted subtly at the mention of Tanjiro.
Kokushibo continued.
"If his belief collapses, he will hesitate. And hesitation creates openings."
Muzan exhaled slowly.
"…So you are saying we don't kill him."
"Yes."
Kokushibo's voice lowered.
"We reshape him."
Muzan considered this in silence.
Then a faint smile formed.
"I see…"
Nakime appeared briefly at the edge of the chamber, adjusting space silently.
Muzan spoke again.
"Bring me a disguise."
Moments later, through Nakime's Blood Demon Art, Muzan reappeared in an altered feminine human appearance.
Kokushibo remained unbothered.
Muzan adjusted his posture.
"Continue."
Kokushibo observed him for a moment before speaking again.
"That boy is likely connected to Yoriichi Tsugikuni."
At the name, Muzan's expression tightened instantly.
Kokushibo watched carefully.
"Then if we fracture his conviction," he continued, "we do not merely defeat him."
"We symbolically defeat Yoriichi as well."
Muzan's eyes narrowed, thinking.
"…That would be ideal."
Kokushibo's words had found their target.
Yoriichi remained the deepest wound in Muzan's existence.
Any path that led back to victory over him direct or indirect was irresistible.
Muzan stood slightly.
"Then I will handle him."
Kokushibo raised a hand slightly.
"Not yet."
Muzan paused.
Kokushibo continued calmly.
"If he breaks too quickly, he becomes meaningless."
"He must fracture slowly."
Muzan stared at him.
"…You are unusually cautious."
Kokushibo replied without hesitation.
"I prefer certainty over waste."
Far away, within the Elysian Cult grounds, Douma stood in a courtyard under overcast skies.
Kotoha was cleaning nearby.
The absence of sunlight made daytime movement possible for him, and he observed her quietly.
"Master, are you going out?"
Her voice was gentle.
Douma smiled faintly.
"I was thinking about it."
Kotoha hesitated slightly.
She understood what "going out" meant.
Even after everything, she could not stop him from being what he was.
Douma suddenly became quieter.
"Kotoha… avoid going out alone during the day."
Kotoha blinked.
"Why?"
Douma's expression softened in a way that was almost unfamiliar.
"A disturbance recently occurred near human settlements."
"There are things even I do not fully understand yet."
Kotoha nodded slowly.
"Alright. I understand."
She smiled, trying to ease the mood.
Douma smiled back.
But behind the estate's entrance, a faint presence flickered briefly
then vanished.
Douma tilted his head slightly.
"…Strange."
But he did not pursue it.
Instead, he turned back toward Kotoha.
"Come on. Let's continue your story."