What is a Demon?
In Roy's view, "Demons" had not escaped the concept of "human."
They were an amalgamation of all "dark" human emotions—"brutality," "cruelty," "madness," and so on—amplified by Muzan's blood... much like "post-mortem Nen" is born from "obsession" and "resentment"...
Because they "couldn't obtain" something in life, they desperately tried to compensate after becoming a Demon...
His nostrils flared, instantly "sniffing" out the Clone Demon's scent. Roy activated [En] and instantly locked onto the Clone Demon's position, listening in on its "inner voice" and "past" at the same time...
It was just as it had said to Tanjiro in the original story... "Women must be eaten while they are 'young.' If they get older, they become ugly and taste bad..."
Roy sharply captured the "deep self-loathing" hidden in the depths of the Clone Demon's heart.
Because he was poor, old, ugly, and cowardly, he had never married in his entire life, nor had he ever even held a woman's hand. He could only secretly peep on or even stalk young girls... to relieve his inner pressure. Living like a walking corpse was worse than... death!
"Sun Breathing, Second Form: Clear Blue Sky..."
The sword left its sheath, turned red, and flames ignited spontaneously... A blade of light wreathed in fierce fire flashed...
A muddy swamp suddenly appeared on the alley wall. Gurgle... Two demon heads rolled out, and a Clone Demon with two horns on its head fell to the ground... Roy was unhurried. He pointed his sword down and thrust it into the demon's mouth. At a certain moment, his gaze froze. Through the Clone Demon's scarlet eyes, he saw another pair of eyes!
The owner of those eyes had blood-red pupils and was dressed as a "young master," wearing a small suit with suspenders and a pair of shiny leather shoes. He was holding a book, looking up information in an elegant and "luxurious" study, with a few maids standing nearby...
'Muzan?'
'A Crimson Sword... those Hanafuda earrings...'
The two stared at each other through the Clone Demon's pupils, both stunned.
Roy reacted first. His ink-black pupils whooshed and "ignited" into two suns, piercing straight through the Clone Demon's pupils to glare fiercely at what was "inside"...
The first thing Muzan saw were "two suns." Thud, thud, thud... He stumbled back several steps, the book in his hands flying from his grip in terror. Caught off guard, he fell to the ground!
"The sun... Sun Breathing... That swordsman... He's a successor of Yoriichi Tsugikuni!"
BANG! The "Muzan" blood inside the Clone Demon exploded!
The Clone Demon burst apart like a watermelon struck by a hammer...
The faint connection established with Muzan through the demon blood was completely severed!
A panel notification... ["Life Energy" +10... [Monster Encyclopedia] has been updated..]
[Clone Demon: D-Class Monster]
[Constitution: 103 (Note: Average human is 1)]
[Innate Blood Demon Art: Swamp Space (Note: A spatial ability. Using the Clone Demon as the epicenter, a swamp can be opened on any "solid surface" (like a wall or floor) within a ten-meter radius, allowing emergence from it to achieve "spatial leaping")... Now extracted...]
[Innate Blood Demon Art: Clone (Note: A physical clone. Requires a "corpse" as a medium. By infusing demon blood, the corpse is reshaped)... Now extracted...]
Whoosh... [Eye of Delusion Breaking] extinguished.
Roy sheathed his sword. "He fled pretty fast."
As his thoughts turned, he received the two streams of information from the panel...
A swamp appeared at his feet, and he immediately sank into the ground. When he reappeared, he was ten meters away, poking his head out from the corner of a wall... Just like that, sometimes sinking, sometimes surfacing, he used the swamp to shuttle through the streets and alleys, silently familiarizing himself with [Swamp Space]. A moment later, he left the Demon Slayer world and returned to the Hunter world...
"Young Master..."
"Young Master..."
"What's wrong?"
Tokyo.
Inside a certain luxurious mansion.
Seeing their young master fall, the maids reached out to help him. Their arms were extended, but their heads were gone. Muzan, disguised as a "boy," punched and killed the maids, one by one. He sat disheveled on the floor, clutching his chest and gasping for breath... It had been hundreds of years. Ever since the death of that swordsman with the flame Mark on his forehead, he had never felt "fear" like this again!
Those Hanafuda earrings... that Crimson Sword wreathed in roaring flames... those "Great Sun pupils" that stabbed straight into his heart... In an instant, they dragged him back to the bamboo forest where he first encountered Yoriichi Tsugikuni!
That night, the bamboo forest rustled in the wind...
He had mocked him as just an ordinary swordsman; he had been shattered into more than 1,800 pieces...
He had said: "I am no longer interested in swordsmen who use Breathing Styles."
He had asked: "What do you take life for?"
Muzan dared not forget... Whether it was the Mark... or the Crimson Sword... even the earrings that Yoriichi Tsugikuni once wore, hundreds of years had passed, but he still dared not forget!
"Nakime, convene an Upper Moon meeting. I want..."
"That swordsman... dead!"
Veins bulged around the boy's savage, blood-red pupils!
He climbed up from the pool of blood and filth, saying just that... This night, the sky was turbulent, vastly different from any ordinary night...
There were Demons eating people, the Demon Slayer Corps hunting them, Upper and Lower Moons gathering from different corners to one place, and Ubuyashiki Kagaya listening to Gyomei Himejima chant sutras, holding a hand warmer and draped in a cloak, gazing at the stars...
Everyone, every demon, showed their own colors. Only... the one stirring up the situation, as always, followed the chiming of the grandfather clock in the corner...
At 4:30 in the morning.
He passed through the "dream tunnel," left the Demon Slayer world, and returned to the Hunter world.
He opened his eyes right on time. This time... Roy looked through the window at the pre-dawn darkness. He didn't roll out of bed. Instead, still on the soft mattress, he summoned a patch of swamp and sank straight down. When he popped up again, he emerged from the ancient stone corridor outside his door!
[Swamp Space] ignored terrain, allowing free travel within a ten-meter radius. It seemed... even more useful than Roy had imagined.
The corner of the boy's mouth lifted slightly. He did some simple stretches and began his morning run around Kukuroo Mountain.
He passed through the long corridor, rounded the corner, and ran under the stars, heading down from the castle's main gate.
After he left, in a dim little room, a certain old man was listening to cartoons, a blanket over his lap, rocking in his chair. His closed eyes slowly opened a crack, and he smiled coldly at a dark corner. "A certain brat's 'concealment technique' is much better than a certain grandfather's."
The "darkness" stirred... A head of showy white hair appeared, and Zeno walked out with his hands behind his back. He respectfully called out, "Grandfather."
Maha closed his eyes, not even bothering to look at him, just sneering, "Oh... isn't this Zeno... Isaac?"
"You finally willing to come back from your father Netero's place?"
Zeno: "..."