"It's a success... a preliminary success!"
Tamayo's voice was filled with barely suppressed excitement.
In her hand, she held a test tube containing a clear liquid that emitted a faint golden glow.
Cheng Mo immediately walked closer.
Tamayo handed him the test tube, speaking quickly: "This is the serum combined with the Colored Glazeblood. Mr. Cheng Mo, your observation was correct; that special component can indeed form an extremely thin, pale golden protective film on the outer layer of soul energy, effectively blocking the corrosive signals of the 'fragments.'"
"And with the latest purified wisteria flower essence I extracted, it has a peculiar burning and inhibiting effect on that dark soul energy..."
A faint light flickered in Cheng Mo's eyes, and the Eye of Truth confirmed the energy structure of the medicine.
The pale golden protective energy combined skillfully with the purifying energy of the wisteria flower medicine, forming a gentle yet resilient barrier.
"An inhibitor."
He named it.
"Yes, an inhibitor!"
Tamayo nodded excitedly.
"Preliminary in vivo tests have shown significant results; it can effectively reduce the activity of demon blood and greatly weaken the urge for blood!"
But they soon discovered that the effect of this inhibitor was gradient.
It worked extremely well on the low-level demons Cheng Mo captured, almost temporarily restoring them to a state close to human.
However, its effect was greatly diminished on the "fragments" extracted from Upper Rank demon blood samples.
It could only provide temporary inhibition and weakening, not eradication.
"Within the Upper Ranks, Muzan's soul fragments are far stronger and of higher quality than those in ordinary demons."
Cheng Mo analyzed calmly.
"A more potent formula is needed, or... a method that directly targets the core."
At the same time, Cheng Mo began another dangerous attempt.
He concentrated all his mental energy, and the Eye of Truth locked onto one of Hantengu's wildly roaring soul fragments.
Simultaneously, the powerful mental energy honed by the Heart and Soul Secret Canon acted like the finest probe, cautiously tracing backward along the invisible channel that the fragment emitted, connecting to its distant main body.
In an instant, a complex and chaotic information stream, like a breached dam, surged into his consciousness!
That channel was infinitely more complex than he had imagined, twisted and winding, filled with the mental pollution left by Muzan.
Moreover, the control was entirely at the other end—
In Muzan's hands!
Cheng Mo immediately cut off the connection, his face slightly pale.
Even a momentary attempt consumed an immense amount of energy and carried extremely high risks.
"No," he told Tamayo, "the channel is entirely controlled by him, incredibly complex. Forcing my way in would definitely be noticed immediately."
But he was not without gains.
"I've initially figured out the characteristic energy fluctuations of this connection... it's like identifying a unique 'frequency.'"
A sharp glint flashed in Cheng Mo's eyes.
"This might... provide a possibility for us to locate him in the future, or to perform more precise demon blood stripping."
The laboratory once again became busy.
The essence of demon blood was peeled back layer by layer, and a theoretical "stripping method" was also developed by Cheng Mo and Tamayo.
Through high-intensity, high-precision soul energy impact, combined with specific frequency resonance, it was theoretically possible to "shatter" or "strip away" Muzan's soul fragments, which were like parasites.
This method had been repeatedly deduced and verified on paper.
It was like surgery at the soul level.
Cheng Mo speculated that this method could allow demons to break free from Muzan's control while retaining some abilities, just like Tamayo.
But theory ultimately required clinical practice.
Cheng Mo stood before the experimental bench, his gaze sweeping over the precious samples.
He needed a suitable experimental subject, one that met several stringent conditions.
This was to ensure that Muzan's soul fragments were sufficiently complete and active, possessing value for research and stripping.
However, Tamayo and Himura Senichi, who had already broken free from Muzan's control, obviously did not meet this condition.
The Muzan fragments in Tamayo's blood were so weak as to be negligible, while those in Himura Senichi's body had formed a strange balance and symbiosis.
Moreover, the subject had to be in an extremely weakened or absolutely tightly controlled state to ensure the safety of the entire high-risk operation.
Thinking of this... a figure frozen for a century surfaced in his mind.
He walked to the corner of the laboratory and gently raised his hand.
The Silent Shadow Crow, which had been quietly perching, silently landed on his raised arm, its crow eyes deep.
"Black Feather, go to the cave where the Kamiyakawa sisters are sealed."
Cheng Mo's thought echoed in Black Feather's mind: "Inform them that the method for stripping Muzan's curse is theoretically complete. Now, a clinical validation is needed. Ask them... if they are willing to try it."
"However, the process will be extremely painful, with an estimated success rate of no more than seventy percent. Failure could mean the complete annihilation of their souls."
Black Feather elegantly tilted its head, and a deep, magnetic voice sounded: "Understood, Master."
It flapped its wings and soared, transforming into a streak of light that almost merged with the shadows, silently passing through the laboratory's ventilation ducts and disappearing.
A day later, Black Feather returned, landing on Cheng Mo's shoulder and preening its feathers with its beak.
"Master, the message has been delivered, and Kamiyakawa Hotaru has responded."
Black Feather's voice directly entered Cheng Mo's mind.
"She said: 'As long as there's a glimmer of hope to free my sister, no matter how painful, we are willing to endure it.'"
A flash of understanding crossed Cheng Mo's eyes.
This answer was within his expectations.
He did not leave immediately.
Instead, as usual, he went to Mount Momoyama again, "honing" Tanjirou and Zenitsu with lightning and soul pressure, as if everything was normal.
Old Man Kuwajima still watched the spectacle, and the two boys still complained bitterly.
Everyone was accustomed to his occasional disappearances and appearances.
It wasn't until late one night that Cheng Mo quietly left his hiding place in Asakusa.