Rokuro's mental network continuously expanded as more people drank from the well.
Some of the parasitized residents even unfortunately encountered demon attacks at night and perished, and their mental imprints were then transferred to the evil demons that preyed on them.
This allowed Rokuro's "eyes and ears" to extend into darker corners.
Just as he was building an invisible and vast intelligence network for himself, secretly feeling pleased...
a sudden change occurred.
He felt that the mental imprints he had dispersed began to disappear one after another, rapidly!
It wasn't a natural dissipation, but rather an instantaneous annihilation by some violent and pure force!
He concentrated his consciousness with suspicion and uncertainty, "seeing" through an imprint that had just transferred to a mountain demon.
It was a black-haired youth wearing a black haori, with an indifferent expression.
His movements were as swift as a ghost, and each swing of the long nichirin blade, wrapped in terrifying lightning, precisely severed a demon's head.
Just before the imprint was completely annihilated, Rokuro clearly "felt" that power.
Violent, destructive, with a shuddering palpitation and numbness that made his soul tremble.
Merely perceiving it from a distance made him feel as if his spirit was being scorched by tiny electrical sparks!
"!!!"
Rokuro abruptly cut off the connection, his heart pounding, his back instantly drenched in cold sweat.
It was him!
The dangerous individual that Muzan-sama spoke of!
This kind of power... it's simply unheard of!
What made Rokuro even more terrified was that the moment Cheng Mo casually annihilated the demon... those cold eyes seemed... seemed not entirely focused on the demon in front of him.
His gaze was terrifyingly sharp, as if it pierced through the demon's body, through the obstruction of space, and landed precisely on him—
On Rokuro's true body, hiding and peeking from afar!
An extreme chill, like being targeted by a natural predator, crept up his spine and spread throughout his body.
"Impossible... how could he have discovered..."
Rokuro desperately denied it in his heart, but the unsettling feeling of being completely exposed lingered.
Fear finally overwhelmed all curiosity and desire for merit.
He completely reined in all his aura, dormant like the humblest insect.
Rokuro cautiously manipulated his remaining mental imprints, keeping them as far away as possible from the areas Cheng Mo frequented.
He dared not make any further moves.
He couldn't afford to take this risk.
On the other side, Cheng Mo, who had just casually dealt with a demon, sheathed his startled insects, and the lightning receded.
He stood in place, his brows slightly furrowed.
The faint golden glow of the Eye of Truth had not yet completely dissipated.
In the past few days, when he slew certain demons, he always felt something was amiss.
It wasn't that the demons themselves were particularly strong.
Rather, at the core of their disintegrating body energy, there would occasionally remain an extremely faint mental imprint, completely different in nature from demon blood energy.
The imprint was very subtle, like a drop of ink in water.
It would quickly be completely purified by the violent power of lightning when the demon was killed, but his Eye of Truth still captured that momentary anomaly.
"A kind of... mental probing mark?" Cheng Mo pondered.
"Is someone... or rather, is some demon, observing through these low-level demons?"
This feeling was very subtle, carrying an unpleasant sense of being spied upon.
Based on the original information, he generally had an impression of the abilities of the Upper Moons, and none seemed to perfectly match.
Therefore, the possibility pointed to the Lower Moons whose abilities were not extensively displayed in the original work and were later eliminated by Muzan.
"Has one of the Lower Moons sneaked over?" Cheng Mo's eyes grew cold.
Was the target the Butterfly Mansion? Or Himura Senichi?
Or... was it just a widespread reconnaissance?
His expression remained normal as he cleared the scene, as if he had discovered nothing.
He even deliberately maintained a relatively regular hunting route and frequency, not immediately showing any signs of vigilance or large-scale searching.
Startling the snake would be no fun.
Cheng Mo thought.
Since you want to watch, then let you watch... The night was deep, and the remote village had long since extinguished its lights.
Only a few scattered points of dim yellow light flickered weakly in the darkness.
Not far away, a waterfall roared, and mist filled the air.
Fierce fighting and roaring broke the silence of the night.
Four Demon Slayer Corps members were engaged in a bitter struggle.
Their opponent was an unusually large demon, nearly three meters tall, covered in exaggerated muscles.
Its face was covered with crisscrossing, ugly scars, a veritable giant butcher crawled out of hell.
The Butcher Demon wielded a giant bone-cleaving knife, stained with shredded flesh and blood, each swing accompanied by a terrifying whoosh, kicking up large amounts of dirt and dust.
"Water Breathing, Third Form: Flowing Dance!" one member tried to use speed to outflank and attack.
However, when his nichirin blade struck the Butcher Demon's thick arm, a strange red glow instantly surged beneath the skin of that area.
Its muscles writhed and proliferated wildly like a living thing, suddenly swelling into an incredibly tough tumor of flesh!
Clang!
The sound of metal clashing rang out, and the nichirin blade was actually repelled!
It only left a shallow wound on the tumor, splattering a few strands of foul-smelling black blood.
"Be careful! Its blood is poisonous!" another member, who was providing support, hastily warned.
But it was already too late.
A good amount of the splattered black blood landed on the face of the member who had just attacked.
"Ugh ah—!"
A shrill scream immediately erupted.
The member's cheek was as if splashed with strong acid, his skin rapidly blackened, festered, and sizzled with white smoke.
He writhed painfully on the ground, instantly losing his combat ability.
"Sato!" the remaining three exclaimed, their minds momentarily distracted.
In that instant, the Butcher Demon seized the opening, and its huge fist slammed out like a battering ram!
Bang!
Another member failed to dodge and was directly hit in the abdomen.
He flew backward more than ten meters like a broken kite, crashing heavily into a tree.
Then he slid down, his fate unknown.
In the blink of an eye, only two of the four-person squad remained standing.
Looking at their companions, instantly halved, the remaining two members' faces drained of color, and despair inevitably surfaced in their eyes.
The disparity in strength was too great!
"Ho ho ho..."
The Butcher Demon's huge mouth suddenly split open, tearing all the way to its ears.
It revealed a mouth full of bloody, jagged fangs.
Its voice was thick and hoarse like a broken gong, filled with cruel pleasure: "Demon Slayer Corps members... I love to eat them the most! You practice that Breathing Technique, right? Your meat is much tougher than ordinary people's, it's especially satisfying to chew!"