Escorted back to Peach Mountain by the Kakushi, Ryosuke had barely stepped inside before Rika threw herself into his arms and burst into tears.
Shota, as usual, hid in the shadow of the doorframe, peeking from the darkness.
The sound of grinding teeth came one after another.
The resentment radiating off him was practically tangible—enough to sustain three evil sword immortals.
Tch. Useless big brother…
Ryosuke couldn't be bothered with him. He rubbed Rika's head gently.
"Why are you crying? I'm not dead, am I?"
"But—but what if something really happened to you?" Rika sobbed, tears welling in her eyes.
"It won't. Your big brother here has ridiculous luck. I won't die."
The last three words stuck in Ryosuke's throat.
"Luck, my ass!"
Jigoro hurried over with his cane. He raised it, intending to rap Ryosuke on the head—but seeing his injuries, he couldn't bring himself to do it.
"You completed the mission. Why did you still go out of your way to put yourself in danger?"
"Grandpa, even if I hadn't killed that demon, someone else would have."
What Ryosuke meant was that he didn't want anyone stealing his kill.
To him, those demons weren't demons at all.
They were adorable walking bundles of experience.
"You child…"
Jigoro sighed.
Clearly, he had misunderstood Ryosuke's meaning.
He thought Ryosuke was acting out of concern for others.
It wasn't a bad disposition—but it was the kind that got people killed.
Breathing techniques had remarkable effects on healing. In half a month, Ryosuke's injuries were completely gone.
During that time, Shota also received and completed his first mission.
There was no helping it—too many had passed Final Selection, and too few suitable demons remained for rookies to train on.
Ryosuke sat at the edge of the training ground, deliberately slowing every inhale.
The airflow felt almost tangible, carrying the stagnant impurities from within his body. A faint, persistent sting followed him like a shadow.
Total Concentration Breathing: Constant.
This was Ryosuke's main focus lately.
Put simply, it meant turning Total Concentration Breathing into a habit.
Eating. Sleeping. Using the bathroom. Playing cards.
Every moment—Total Concentration.
This was the foundation of Breathing Techniques, the key to prying open the body's limits. Incredibly important.
In gamer terms: Total Concentration was like activating an ultimate buff.
Once you mastered Constant, you could keep it active nonstop—turning an active skill into a passive one.
"Breathing isn't about forcing it. It's about becoming one with it," Jigoro instructed calmly.
"Lightning doesn't only exist in the moment of release. It is constantly forming deep within the clouds—stored, restrained. When it finally erupts, its power is far greater."
Ryosuke tried again.
Still failed.
This kind of cultivation couldn't be rushed.
More than technique, it demanded habit.
After all, even the protagonist Tanjiro had been tormented half to death while learning Constant.
[Heehee~ Host, for just one tiny year of lifespan, you could instantly master Constant, you know~]
The system's tempting voice whispered in his ear.
"One year…"
[Yes yes! Such a great deal, right~]
Listening to that infuriatingly smug tone, Ryosuke had reason to suspect the system was skimming something off the top.
[Dear~ host~ Have you decided yet?]
"It would be convenient," Ryosuke admitted with a smile—then added immediately,
"Da ka ko to wa yuranai!"
You… refused?!
System: (゜д゜)
How—how is this guy not falling for it?!
Ryosuke rolled his shoulders.
On one hand, he needed to save up ten years of lifespan to fix his liver.
On the other…
Forget a year. Even without the system, he could master Constant within half a year.
His current demon kills were limited. Missions weren't daily. Lifespan income was extremely tight.
In his previous life as a hoarder and hardcore gamer, Ryosuke understood one thing very clearly:
Early-game resource management and cautious growth were everything.
If he splurged now and ran into a Lower Rank later without enough lifespan to spend, he'd be picking up a death box on the spot.
More importantly—combat experience, reaction speed, physical conditioning.
These crucial factors couldn't be bought with system points.
True strength had to be forged.
A peerless sword in the hands of an infant was pure waste.
For Ryosuke, the system was his greatest trump card—his final safety net. If he could save it, he would.
Once he became a Hashira and had his own territory, he could enter full-on farming mode—harvesting lifespan without hesitation.
But for now, steady progress was the way.
Just then, a familiar deep-blue figure swooped down and landed on his shoulder.
"Caw! Yasui Ryosuke! Mission!"
"Kanagawa Prefecture! Multiple young women have vanished at night—investigate immediately!"
Before Ryosuke could fully process that, the hummingbird spoke again.
"Additionally! By the Master's assessment—Yasui Ryosuke is promoted to Kanoe rank! Caw!"
Not only Ryosuke—even Jigoro froze for a moment.
Rika blinked, staring at Ryosuke with shining eyes full of admiration.
"Wow! Big Brother Ryosuke is amazing! You're Kanoe already!"
Ryosuke's lips twitched.
The Demon Slayer Corps' hierarchy was strict. Higher-ranked swordsmen could command lower-ranked ones.
Each promotion required missions and accumulated merit.
He had only killed some small fry and one troublesome Rokurokubi—and jumped straight from Mizunoto to Kanoe?
That speed was insane.
And with higher rank came more dangerous missions—and stronger demons.
Which meant Ryosuke would be facing even greater pressure and danger with this busted body.
Ubuyashiki Kagaya, you little—!
Ryosuke roared internally.
At the same time, he was grateful Shota hadn't returned from his mission yet.
If Shota found out he'd reached Kanoe already…
That fragile, competitive teenage heart would probably explode on the spot.
Just imagining Shota's twisted "Why are you faster than me?" expression made Ryosuke's head hurt.
"Got it," Ryosuke said, suppressing his complaints as he began packing.
Along the way, he thought about the mission location.
It wasn't far from Asakusa.
That made his heart stir.
Asakusa was loaded with significance.
That's where the beautiful married woman lived.
In the original story, Tanjiro met Tamayo and Yushiro in Asakusa.
By this point in time, Tamayo had already been hiding there for quite a while.
The mission site was close enough that, once finished, he could try his luck.
After all, if he wanted to kill that trash boss Muzan, Tamayo's medicine was indispensable.
The sooner an alliance formed, the faster things would move forward.
With that in mind, Ryosuke quickened his pace.
Several days later, Ryosuke arrived in Kanagawa Prefecture in plain traveler's clothing, blending into the crowds.
He gathered information at teahouses, docks, and marketplaces.
"Ah… another one gone. Miss Okiku from the West Street tofu shop—such a good girl. Two nights ago she said she was taking a bowl of hot soup to her sick granny… never came back."
"Yeah! That's six already! Alive or dead, nothing—like they were swallowed by the night!"
"The authorities investigated again and again—useless! Not even a footprint!"
"Creepy stuff… some folks say they heard strange singing late at night…"
"Yeah! I heard it too! Gave me chills!"
An old fishmonger lowered his voice.
"They say those girls all received seashells before disappearing."
"Right—just ordinary little shells you find by the shore. Not worth anything."
He leaned closer, still uneasy.
"Apparently they just showed up on the girls' windowsills. No one thought much of it at first. Then… well."
Ryosuke nodded and bought a few salted fish from the man.
This mission's difficulty was clearly no joke.
This demon was nothing like the ones he'd killed before.
It had a clear mind and selected its prey deliberately.
Seashells and singing—likely tied to its Blood Demon Art.
He'd have to investigate at night.
Night fell.
Kanagawa was wrapped in suffocating fear. Doors and windows were shut tight.
Only two figures walked the streets, out of place.
The girl clutched the young man's sleeve tightly, her body trembling as she looked around nervously.
"Ken… maybe we should go back. So many girls have gone missing lately—it's terrifying…"
The young man puffed out his chest and smiled.
"What are you scared of? Just rumors. The authorities said it's traveling kidnappers. With me here, no one's touching you. Don't scare yourself."
He patted her icy hand reassuringly, his tone softening.
"Besides, the moon's so beautiful tonight. It'd be a waste not to enjoy it."
The moment he finished speaking, a faint humming drifted into their ears—thin as spider silk, utterly without warning.
The melody was strange and ethereal, neither male nor female, carrying a sticky, seductive pull that drilled straight into the skull and coiled around the brain.
"S-sing… singing?"
Ken turned sharply, trying to locate the source—but his vision blurred rapidly.
He tried to call out to the girl, but no sound came from his throat. His body collapsed heavily as consciousness slipped away.
The girl, who had been trembling in fear moments ago, gradually calmed under the song's influence, her expression turning blank and numb.
She stared into the depths of the street—and began to walk forward.
Like a sleepwalker.