Meanwhile, Rokuro, Lower Moon Two, hidden deep within the shadows of the mountain forest surrounding the Butterfly Mansion, was probing the surrounding environment with his countless silently dispersed "mental seeds."
The mental seeds, like an invisible network, continuously and cautiously sensed the energy fluctuations near the Butterfly Mansion.
After several days of probing, the most heart-palpitating, violent thunder aura, which felt like a natural enemy, had completely disappeared.
Cheng Mo had indeed left.
Confirming this, Rokuro felt an uncontrollable surge of ecstasy.
A chance!
A once-in-a-lifetime opportunity had finally arrived!
He no longer deliberately suppressed his probing intensity.
More, almost invisible, mental spores were silently released by him through underground water veins, especially the well that the Butterfly Mansion relied on for survival.
Through the "vision" of the Butterfly Mansion staff and injured individuals who had drunk or used the well water, Rokuro greedily spied on the internal situation of the Butterfly Mansion.
He "saw" the busy pharmacy, the wards filled with injured people, and the hurried but well-trained members of the "Kakushi" corps.
This was indeed a crucial medical and logistical base for the Demon Slayer Corps!
He even "saw" the Pillar-ranked swordsman who was always stationed there, her face always bearing a gentle smile but exuding an aura that could not be underestimated.
Insect Pillar, Kochou Shinobu!
After the initial ecstasy, a hint of worry surfaced.
The Pillars of this generation seemed significantly stronger than records from the past century; several Lower Moon colleagues had already fallen at their hands.
Although he excelled at stealth and reconnaissance, direct combat was not his strong suit.
Attempting to seize that heavily guarded special sample alone would undoubtedly be suicide.
He must... he must find a way to request reinforcements!
He cautiously transmitted a message to that supreme being through the curse in his blood.
Rokuro's tone was utterly respectful and cautious: "Muzan-sama... the target has been confirmed to be far from its lair, and the lair's defenses are significantly weakened. That 'sample' with special resistance is still in an unstable sealed state..."
"Its energy fluctuations are very peculiar, seemingly resisting your will. Now is the perfect time to capture it and study its mysteries."
He deliberately emphasized the immense research value the sample might hold, implying it could perhaps help Muzan-sama further refine demon blood, doing his utmost to pique his master's interest.
Inside the Infinity Castle, Muzan, who was conducting blood experiments, a cold light flashed in his plum-red eyes.
Cheng Mo's existence was a thorn in his side, and the "sample" of Himura Senichi had aroused his immense curiosity and strong possessive desire.
That "resistant sample" that could resist his will and might even contain the secret to countering his blood was a research object he desperately wanted to get his hands on.
He would never allow such an uncontrollable factor to exist; it had to be under his own control!
"Operation approved."
Muzan's cold voice echoed directly in Rokuro's mind.
"To ensure success, Upper Moon Four, Hantengu, will lead the main attack, responsible for creating large-scale chaos, distracting, and eliminating the Butterfly Mansion's resistance, especially the Insect Pillar."
"Rokuro, you will use your abilities to stealthily infiltrate, responsible for finding and stealing the sample."
He paused, his tone becoming even more cruel and ruthless: "Remember, if the operation fails or you are about to be captured, prioritize self-destruction. Otherwise, you know the consequences."
Rokuro trembled with fear, repeatedly assuring him through the blood curse: "Yes! Yes! I will obey your command, Muzan-sama!"
However, Rokuro, immersed in the joy of receiving support and about to achieve merit, did not notice at all.
Not far behind him, in the inky shadows of the forest, a black crow stood silently on an inconspicuous branch.
Its crow eyes, enhanced by the compass, took in every subtle change in Rokuro's facial expression and the faint energy fluctuations, though silent, that he caused.
That night, in the observation corridor outside the isolation ward.
Himura Ruri watched Kochou Shinobu slowly push a large syringe of sedative into her father's arm.
Watching the transparent liquid disappear, Himura Senichi's struggles gradually diminished, the ferocity in his crimson eyes faded, and he once again fell into a drowsy sleep.
The young girl couldn't help but whisper, "Kochou-san... Father is awake more and more often now. Does he really... still need this much medicine?"
Her voice carried a hint of imperceptible heartache.
Kochou Shinobu, after administering the medicine, skillfully put away the syringe.
She turned to look at the worried young girl, her usual gentle smile receding slightly: "Ruri-san, the dosage of the medicine is to ensure absolute safety. Your father's will is indeed astonishing, but the erosion of demon blood and instinct are even more terrifying."
She paused, a complex and unreadable light flashing in her purple eyes.
"Imagine if he suddenly lost control at this moment and harmed anyone in the Butterfly Mansion... where would that leave Cheng Mo-sensei, who went against everyone to insist on saving him?"
Himura Ruri understood the cautious, businesslike tone in her words, as well as the underlying aversion to demons, stemming from past trauma, hidden beneath her professional demeanor.
Her eyes darkened, and she lowered her head, her fingers unconsciously twisting the corner of her clothes, no longer speaking.
She knew Kochou Shinobu was right... Meanwhile, at the edge of the wisteria tree forest surrounding the Butterfly Mansion.
Two Demon Slayer Corps members, responsible for night patrols and vigilance, were walking along their fixed route.
The taller member yawned, rubbing his somewhat sore eyes.
He whispered to his companion, "By the way, aren't the night shifts too frequent lately? I feel like I haven't rested much. Did something happen?"
The shorter member next to him seemed less concerned. He leaned on his nichirin blade and said lazily, "Who knows? We just do what the higher-ups arrange. But I heard that a very important 'sample' is being treated in the Butterfly Mansion now, so it's normal to be stricter, right?"
When he mentioned the word "sample," his expression was somewhat obscure, with a hint of curiosity mixed with an imperceptible aversion.
The taller member frowned, gently nudged him with his elbow, and lowered his voice: "Hey, you, that word 'sample'... never mention it in front of Ruri-san. And besides, that person was personally saved by Cheng Mo-sama..."
"I know, I know, I just said it casually..."
The shorter member nodded sheepishly, but before he could finish his sentence—
In the shadows beside them, without warning, a figure trembled and "emerged"!
It was a small, old man dressed in rags, looking extremely pitiful.
He had an ugly growth in the center of his forehead, and two small horns grew crookedly on his head.
The old man was trembling all over, tears streaming down his face, muttering incessantly, his voice filled with terror:
"W-w-w... Don't... don't hurt me... So scary... Please let me go..."