Morning light spilled over Asakusa, thick with the scent of everyday life, finally washing away the exhaustion of Ryosuke's night-long sprint.
"Boss, one bowl of noodles!"
Ryosuke sat down at a street stall, still shaken.
Who could understand the terror of a straight man who'd lived in Sichuan in his last life?!
Fasting techniques are supposed to be used for taking dumps, damn it!
After a quick meal, Ryosuke began wandering the streets.
Compared to the remote towns he'd passed through, Asakusa really was on another level.
Street vendors lined the roads, hawking their wares. Rickshaw bells chimed. The smells of rice cakes and fried tempura flooded his senses all at once.
Ryosuke asked around at several pharmacies and traditional clinics in succession. All he got in return were confused headshakes—or wary looks. No one had any information about Tamayo.
"Tch. Looking for a needle in the ocean."
Ryosuke smacked his lips.
Tamayo had managed to hide for hundreds of years right under Muzan's nose—and under the eyes of countless demons. That took more than just Yushiro's Blood Demon Art.
It meant she was absurdly cautious.
Finding her wouldn't be easy.
Ryosuke sighed—and then a blunt, simple idea popped into his head.
If he couldn't find her…
He'd make her come to him.
By midday, a strange rumor began drifting through several of Asakusa's busiest streets.
There was talk of a young outsider seeking medical help. Wherever he went, he sighed heavily, occasionally confiding in overly friendly stall owners in a hushed voice.
"Ah… my older brother must've run into some kind of evil curse. Once he's injured, the wounds heal on their own. He can even walk around during the day like a normal person, but…"
He'd trail off, face twisted in anguish.
"But what?"
Lowering his voice even further, the youth would whisper,
"He can't live without human blood. If he goes too long without drinking it, he loses his mind—suffers terribly."
"I've taken him to countless famous doctors, but none of them can do anything. They only say it's some kind of soul-separation illness recorded in ancient texts. If there's an expert who can cure him… we'd pay any price. Even sell everything we own."
At first, the rumor spread only in small circles.
Soon enough, fueled by gossip and embellishment, it took on a lurid edge.
Some scoffed, calling it nonsense.
Others whispered darkly, claiming it was a curse from a blood demon.
A few even secretly pointed the "outsider" toward obscure shrines, telling him to try his luck there.
Ryosuke moved back and forth between several districts, relying on solid acting to scatter his bait evenly.
He calculated quietly.
Given Tamayo's hatred for Muzan—and her obsession as a doctor—
A rumor about a demon that could walk in sunlight and only needed blood to survive?
That would definitely catch her attention.
At the same time, Ryosuke realized something else.
Yushiro was a demon created by Tamayo, not controlled by Muzan—and he even possessed a Blood Demon Art.
If I start now… find Tanjiro's family, get my hands on the Blue Spider Lily, then have Tamayo turn me into a demon—
Wouldn't I beat that bastard Muzan to the punch and become a JoJo-tier lifeform like Kars?!
Infinite lifespan. Infinite system upgrades.
No more penny-pinching!
Wouldn't that make me invincible?!
Ryosuke was getting carried away when the system dumped a bucket of cold water over his head.
[Dog host, wake up. Stop dreaming~]
"Huh? What—are you saying I'm not allowed to become a demon?" Ryosuke raised a brow.
[Not exactly. I just hope you'll use that dog brain of yours and think it through~]
"Dog system! Your mom—"
Ryosuke cut himself off mid-curse, suddenly realizing the problem.
Yushiro was turned by Tamayo, and he wasn't under Muzan's control.
But there was a fatal flaw.
Time. And probability.
Tamayo had met Yushiro over two hundred years ago.
In those two centuries, she'd treated countless patients.
People with terminal illnesses who didn't want to die were hardly rare.
Yet only Yushiro—and Chachamaru—had succeeded.
When Muzan turned someone into a demon, it was effortless—like flicking water off his fingers.
But Tamayo had modified her own body to escape Muzan's control.
The concentration of Muzan's blood in her was inevitably thin.
Turning a demon back into a human already took enormous time.
Turning a human into a demon took even longer—and that was with Muzan's blood.
Tamayo's would be far weaker.
If even an ordinary human like Yushiro had such low odds…
What about someone like him, who used Breathing Techniques?
The success rate would be abysmal—and the time required absurdly long.
[Mm~ not totally stupid~]
The system yawned.
[If Croc-sensei hadn't patched this later, after Tamayo and Kagaya teamed up before the final battle, there'd be a massive loophole.]
[Just throw out morals and beliefs, turn all the Hashira into demons, gang up on Muzan, then have Yushiro turn them back afterward. No one dies—easy win.]
Ryosuke snorted. "So you've read the original too, huh?"
[Dog host, where do you think the name 'Demon Extermination System' even came from? I'm a diehard fan!]
Ryosuke rolled his eyes.
So much for shortcuts.
Looks like it was back to honest training, honest demon-slaying, and steady growth.
By evening the next day, dusk settled in.
Ryosuke had just sat down at another noodle stall when a blue-haired boy with a sour expression appeared beside his table.
"I heard you're looking for a doctor who can cure strange illnesses," Yushiro said flatly, no emotion in his voice.
Don't smile. Don't smile.
Ryosuke kept his face under control and replied with barely contained excitement.
"You have a lead?"
"Follow me."
Yushiro turned and left.
Ryosuke stood and followed.
They wound through narrow alleys, turning again and again, until the light and scenery subtly warped.
It was Yushiro's Blood Demon Art—concealment.
Ahead, a stone wall rippled like water, sealing off the outside world completely.
Beyond it lay a hidden estate, surrounded by tall trees that blocked sunlight even in broad daylight.
The door stood open.
A woman stepped forward.
She wore a simple, elegant kimono. Her long black hair was tied into a neat bun. Her face was gentle, her presence calm—like ancient jade resting in deep water.
Before Yushiro could speak, Ryosuke let out a low laugh.
"Lady Tamayo. I've heard much about you."
The words were like a boulder dropped into still water.
Tamayo's pupils shrank, her body instinctively leaning back.
A demon slayer?
Or a demon sent by Muzan?!
Yushiro reacted even more violently.
"You bastard!!!"
The shout exploded with rage.
Ryosuke didn't waste words. In an instant, he pinned Yushiro's arms, slammed him to the ground, and stomped down hard!
Yushiro let out a muffled groan—his spine felt like it was about to snap.
He struggled instinctively, but the foot on his back was as heavy as a mountain. No matter how hard he fought, he couldn't break free.
Ryosuke didn't even look at him.
His gaze never left Tamayo.
The curve of his lips deepened slightly.
"Lady Tamayo. I know who you are. I'd advise you not to move."
He drew his Nichirin Blade and stabbed it into the ground. The pearly-white edge radiated a chilling cold.
"If you activate a Blood Demon Art, I'll kill him."
"Stop! Let Yushiro go!"
Tamayo cried out.
Her hand, hidden in her sleeve, slowly fell back to her side.
"Don't worry about me, Lady Tamayo! Run! Get away!!"
Yushiro roared, veins bulging on his forehead.
This guy would rather die than let Tamayo come to harm.
Top-tier simp. Even Boar-Headed Inosuke would hand him a cigarette in respect.
Tamayo sighed softly.
Run?
Where could she run?
This demon slayer had found her, spoken her name—he was clearly prepared.
And his strength was far beyond anything she and Yushiro could resist.
Several long seconds passed.
Tamayo took a deep breath, as if resigning herself to fate, and withdrew her hands from her sleeves.
"You win."
Her voice was dry, exhausted.
Since breaking free of Muzan's control, she'd lived wedged between humans and demons.
Muzan wanted her dead as a traitor.
The Demon Slayer Corps killed demons on sight.
She belonged nowhere—alone, and tragic.
"Who are you," she asked quietly, "and what do you want?"
Seeing her forced submission, something strange flickered through Ryosuke's chest.
Yushiro, you useless simp…
So this is what it feels like to be the NTR villain?
Huh. Kinda complicated.
Ryosuke raised a brow and smiled, his tone relaxing.
"It's simple, Lady Tamayo. I'm not here to hunt you."
Tamayo looked at him skeptically.
Ryosuke continued, "I want to talk business."
She clearly didn't believe him.
A demon slayer shows up at a demon's hideout, draws a Nichirin Blade, steps on her companion—and says 'business'?
"Yes. Business."
Ryosuke nodded, smile unchanged.
"I want to kill Kibutsuji Muzan."
The name fell like a forbidden curse.
The air froze.
Tamayo's body stiffened, emotions flashing across her face.
Every demon slayer wanted Muzan dead—that wasn't unusual.
But Tamayo was different.
Turned into a demon by Muzan, she'd devoured her own husband and child in a moment of starvation.
She'd lived until now for one reason only—
To drag that bastard Muzan into hell.
But killing Muzan…
This demon slayer was strong, yes—but compared to the Upper Moons, the gap was still enormous.
Killing Muzan with his strength?
Ryosuke saw the doubt in her eyes and explained calmly.
"If brute force were enough, Muzan would've died long ago."
"I need your expertise. I need you to develop a drug that can turn demons back into humans."
"That is the true weapon—one that can sever Muzan's power at its root, and deal him a fatal blow."
Advance Chapters available on Patreon
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