After Ubuyashiki Takuto and his wife left the room, Yosuke had just begun to relax when the door opened once again.
He glanced sideways—and to his surprise, it was Ubuyashiki Muzan, bracing himself against the wall, forcing his frail body into Yosuke's room.
Muzan glared at him with venom:
"It's you… it's all your fault! Because of you, stealing my nourishment in the womb, I was born into this wretched state—neither man nor ghost!"
Yosuke's pupils shrank sharply. You're seriously blaming me for that? Are you out of your mind?
Oh. Right. It's the future boss himself. In that case, makes sense.
"I want to kill you so badly…! I want to kill you, and then kill Father and Mother too! Everyone who made me suffer—they all deserve to die!"
Muzan collapsed to the ground, crawling toward Yosuke step by step.
Fear gripped Yosuke. He wanted to cry out, to flee, but his body refused to obey. He could only watch in terror as Muzan crept closer.
At the last possible moment, Muzan's maid appeared in the doorway.
"Master Muzan! What are you doing here? Your body can't handle this kind of exertion! It's already late—if you wish to see Young Master Yosuke, I'll bring you tomorrow instead!"
Without leaving room for protest, she carried Muzan back to his room.
Yosuke's chest heaved painfully. He wanted to breathe deeply, but his weakened body could not keep up. The suffocation nearly made him faint.
As he slipped into unconsciousness, he heard the maid's words about bringing Muzan again tomorrow. His heart screamed in silence:
"Don't come back!"
The next day, true to her word, the maid wheeled Muzan into Yosuke's room.
Yosuke's eyes filled with dread. You really came back?!
Yet this time, Muzan's demeanor was completely different. Gone was the murderous rage. He stared at Yosuke with a cold, detached expression—as though looking down at an insect.
In a chilling voice, Muzan said:
"Starting tomorrow, I'll live in the clan's separate residence."
The maid froze. Yesterday they were still a harmonious family—how did it come to this overnight?
Yosuke exhaled in relief. Though he hated Muzan's contemptuous gaze, at least he was safe—for now.
Six more years passed.
At sixteen, both Muzan and Yosuke's conditions had only worsened.
Though Muzan still appeared functional—able to eat and move about—his internal organs were failing. His current vitality was little more than a final flare before death.
As for Yosuke, he was little more than skin and bones, muscles wasted away. His breathing was so faint it seemed each moment could be his last.
Now, at death's door, Yosuke no longer knew if he would ever open his eyes again. His body's suffering had reached its limit. Part of him simply wished for release.
What Muzan? What Demon Slayer Corps?
I'm about to die. Where would I even find the strength to care about that?
As his life flickered, Yosuke's memories spun before him like a revolving lantern.
Sixteen years ago, he was born into this world. At age three, his memories of his past life awakened, and with them, the knowledge that this was the world of Kimetsu no Yaiba.
At first, he dreamed of surviving long enough to witness the birth of Yoriichi Tsugikuni, to learn the Sun Breathing and one day face Kibutsuji Muzan. But that was centuries in the future—his heart sank at the impossibility.
Reality was harsh. With his feeble body, he spent his days bedridden, relying on bitter medicine just to keep breathing.
At seven, he finally managed to eat liquid food, giving him a sliver of hope. Though he had abandoned the idea of fighting Muzan, he still wanted to live—to one day care for the parents who loved him so dearly.
By fifteen, hope had curdled into despair. He no longer dreamed of survival—he longed only for release. Yet his parents, unaware of his thoughts, clung desperately to the belief they could prolong his life.
And now…
As his revolving lantern faded, Yosuke opened his eyes with effort. His mother's anxious face was before him. He sighed inwardly.
Sixteen years of transmigration, and this is what I got? What a joke…
His thoughts blurred into darkness again. Perhaps this time, he would not wake. Through the haze, he dimly saw his father rush in, dragging a physician by the hand, begging:
"Please, doctor—I beg you! Save my child!"
He did wake.
When Yosuke opened his eyes, the first sight was his parents, gazing at him with worry and relief.
Seeing him conscious, Takuto and Mikako pulled him into their arms, weeping uncontrollably.
I… didn't die?
Yosuke was stunned. He could swear he had just heard his own voice. Was it real?
Takuto and Mikako were just as astonished.
Mikako, trembling, asked:
"Yosuke… did you just speak?"
"…Mother."
It wasn't a dream. He had truly spoken.
Mikako clutched him tightly, as though afraid this miracle would vanish.
A physician in the room, dressed in scholarly robes, spoke calmly:
"My lord, my lady—Young Master Yosuke has only just awakened. He must rest. I must also check on Young Master Muzan—he too has taken my medicine, and should be awakening soon."
At this point, Takuto and Mikako trusted this physician implicitly. It was thanks to his miraculous remedies that their younger son had survived. Now, they could only pray for their elder son as well.
The room fell quiet, leaving Yosuke alone.
He stared blankly ahead—until—
Ding!
Host transformation detected: human to demon. System successfully activated.
Ding!
Awarding host with initial random skill. Open now?
Yosuke's face flushed red, excitement surging uncontrollably.
I knew it! As a transmigrator, there's no way I wouldn't get a cheat system. Heh, heh, heh…
He rubbed his hands together eagerly. "Confirm—open it!"
Ding! Congratulations, host has obtained: Blood Demon Art – Shadow Wolf.
Host: Ubuyashiki Yosuke
Constitution: Primordial Origin Demon
Abilities: Super-speed regeneration, Blood bestowal, Blood Demon Art – Shadow Wolf
Unable to wait, Yosuke immediately tested his new power.
"Blood Demon Art—Shadow Wolf!"
His shadow swelled and twisted, forming into a three-dimensional wolf-like monster. He could direct it at will, commanding it to attack.
Overjoyed with his newfound strength, Yosuke played with it gleefully until the sun rose, its rays spilling into the room.
"Crap! I forgot—I'm weak to sunlight now!"
The instant sunlight touched his backside, searing pain flared as his skin blistered and burned away.
Thankfully, he scrambled into the shadows just in time. In the span of a heartbeat, the wound on his body closed completely, leaving no trace.
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