Mitsuri twirled gracefully, her movements soft yet full of power.
Mitsuri
(cheerfully)
"This training improves flexibility, body flow and stamina. You two will dance along with me!"
Tanjiro immediately nodded, nervous but determined.
Jinwoo crossed his arms:
"...I'll pass."
Mitsuri blinked, shocked.
Tanjiro tried to encourage him silently, but Jinwoo only sighed and backed away.
So Mitsuri started with Tanjiro first.
As the music began, Tanjiro tried copying her steps — elegant spins, shoulder tilts, body swings. He kept messing up, stepping on the ribbon, almost falling, but he never stopped smiling.
His sweat flew everywhere.
Mitsuri laughed like sunshine.
Mitsuri
"You're doing great, Tanjiro!"
Tanjiro
"Hah… Hah… I'll… try harder!"
Meanwhile the demon slayer corps members wearing training uniforms were also forced to dance behind them — but they were stiff like robots, stumbling all over.
One guy tripped and face-planted the floor.
Another yelled:
"I'M A SWORDSMAN, NOT A BALLET DANCER!!"
Jinwoo stood far back, hand on his chin, watching silently.
Even the shadow soldiers in Jinwoo's realm (only he could hear) were whispering:
Igris: "My liege… that dance looks dishonorable…"
Beru: "KIEEEEEK!! If she orders me to dance… I will self-destruct…"
Jinwoo didn't laugh… but he was DEFINITELY holding it inside.
---
"Next… stretching time!" Mitsuri announced.
Every demon slayer instantly froze.
She holds the leg of the first trainee using her leg and SLAMMED it into a perfect split.
The trainee HOWLED like childbirth.
"AGHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!"
Everyone trembled.
Even Jinwoo, who has killed monarchs, internally whispered:
"What the hell…"
Tanjiro's turn.
Tanjiro
(fearful)
"M-Mitsuri-san… maybe gently—"
STREEEEEETCH!
Tanjiro's soul left his body for a second.
"AAAAAAAAAAAAAAAAAAAAAAAAAAAH!!!"
Jinwoo's eyes widened, genuinely impressed that Tanjiro survived.
Then Mitsuri turned to Jinwoo with a bright smile.
Mitsuri
"Your turn!"
Jinwoo closed his eyes.
He faced Monarchs, gods, and the Shadow World — but this was new.
He sat down slowly.
STREEEEETCH!
Jinwoo didn't scream — but his eyebrow twitched and shadow energy leaked out slightly.
All the demon slayers stepped back in FEAR.
Mitsuri panicked and instantly pulled back, bowing like crazy.
Mitsuri
"S-sorry!! I didn't mean to hurt you! Are you okay!?"
Jinwoo took a deep breath, stood up and nodded.
Tanjiro whispered:
"That was… horrifying."
Jinwoo replied:
"Worse than a boss dungeon."
Tanjiro nodded silently.
Both had found new respect — and fear — for Mitsuri's training.
> [Training Complete — Hashira Progress: 3/7]
Reward Granted: 560,000 XP
LEVEL UP!
Current Level: 132→ 135
The glow vanished as quickly as it came
---
After training ended and everyone collapsed like corpses on the floor, Mitsuri cheerfully clapped:
"Yay! You two did amazing! I'm so proud!!"
Jinwoo smiled slightly — he liked her energy.
Then he opened his system quietly:
> "SYSTEM ACCESS — SHADOW EVALUATION"
Target: Mitsuri Kanroji
Scanning honor… ⚙
Blue holographic letters floated.
Tanjiro drank from a water cup and didn't notice, but Mitsuri curiously leaned closer seeing the glowing light.
After 3 seconds, the result appeared:
> Honor Level: ABSOLUTE TRUST & KINDNESS
Corrupted Darkness: 0%
Compatibility with Shadow: 100% (Special Rank: ACCEPTED BY LIGHT)
Jinwoo was shocked — nobody in his world had 100% compatibility except his family.
Then another message popped:
> This soul values love, loyalty, and self-sacrifice.
Recommended Shadow Soldier: Maximum Tier for protection.
Jinwoo placed his hand near the floor.
-
+ Shadow Extraction (Friendly Contract Mode)
+ A huge shadow expanded silently beneath Mitsuri.
+ From inside it, a familiar knight stepped out — the loyal shadow soldier clad in black armor.
+ The shield-bearing warrior of justice:
IRON.
+ Iron knelt before Jinwoo, fist to the ground.
Jinwoo (telepathically):
"Iron. Protect Mitsuri with your life —. Guard her from the shadows."
Iron nodded with pride, then merged into Mitsuri's shadow.
Mitsuri felt a warm energy behind her but assumed it was simply happiness from training.
---
Later that night, Tanjiro and Jinwoo rested at the top floor balcony. Cool wind blew across the forest, and the moon was bright.
Tanjiro
"Today was… intense."
Jinwoo
"She trains the body and the spirit at the same time. Smart."
Tanjiro chuckled… but soon his face shifted.
Tanjiro
"Next… it's Obanai Iguro's training. He… scares me a little."
Jinwoo looked at him seriously.
Jinwoo
"Being scared doesn't make you weak. Running away does."
Tanjiro looked touched.
Jinwoo continued:
"By the way… is Nezuko safe? Where is she staying?"
Tanjiro smiled softly.
"At Urokodaki-san's mountain house. She's safe… but—"
He looked down sadly.
"Nezuko sometimes cries when I'm gone. She pretends she's fine… but she gets lonely."
Jinwoo felt something heavy in his chest.
Cute… but painful.
Jinwoo
"After Hashira Training… I'll go there first. I'll guard her."
Tanjiro's eyes widened.
"You would… really do that?"
Jinwoo
"Children shouldn't suffer alone."
That night, Tanjiro secretly decided: Jinwoo is someone he will trust forever.
---
A soft humming sound interrupted the quiet night.
Something floated up to the balcony — a drone, a bit broken.
Tanjiro jumped back.
"What is that!?"
The drone's speakers activated.
Cha Hae-In's voice emerged: "Jinwoo-san, can you hear me? The anti-mana drone worked. We found the boss...and his domain....The Demon King… is real."
Tanjiro stared in total confusion.
Jinwoo didn't answer.
He stepped forward slowly… picked up the drone… and turned it over in his hand.
The speaker crackled again.
> "Jinwoo… the boss isn't just a ordinary demon king…
It's creating a domain that's there's a tons of demons is here, floating walls, ceeling, doors, etc....
Even I had trouble entering it using this drone."
Her voice trembled — anyone could hear she was hurt.
> "Come quickly. Before it reaches the demon domain too-."
And the audio cut.
The drone's red light died.
Pzzzt… the drone shuts off
Tanjiro swallowed hard. "Is she… someone important to you?"
Jinwoo didn't speak for a moment. He wasn't ignoring Tanjiro — he was thinking.
Two worlds… Two responsibilities…
Right at that moment — across the sky, unseen by humans — hundreds of floating eyeballs appeared around the village.
Tentacles hanging. Pupils dilating, both are didn't noticed.
The Upper Rank 4 symbol burned on them.
Inside Infinity Castle—
Nakime opened her eyes with terror. She was watching Jinwoo… speaking to a machine from another world.
Muzan was reading a newspaper, feet crossed like a king.
One eyeball flashed the image of Jinwoo.
The moment Muzan saw him —
He abruptly stood up.
His hand shook.
A memory he cannot erase — Yorichi Tsugikuni.
But SungJinwoo's aura… was even darker. Even stronger.
Muzan whispered: "…He is not Yorichi. He is something worse."
Nakime trembled — her biwa string nearly slipped.
Muzan's voice then turned sharp:
"Keep watching him. Do not lose sight of him."
Nakime nodded… but inside, she was terrified.