The Demon Slayer Corps Headquarters, hidden deep in the mountains, stood silent like a shrine of war. Cherry blossom petals drifted through the courtyard, beautiful and fragile — a cruel contrast to the reason everyone gathered.
Inside the Great Hall, eight stone sitting platforms formed a circle.
All active Hashira had assembled.
Not for a demon.
Not for a mission.
But for a man.
Footsteps echoed.
Sung Jinwoo entered the hall.
He walked calmly, eyes sharp and unreadable. His presence alone created pressure — not killing intent, not rage — pure dominance, like an apex predator that didn't need to roar.
Mitsuri and Shinobu entered behind him, but took their places among the Hashira instead of following him.
The room tightened.
Sanemi's glare sharpened like knives.
Obanai's grip on his katana turned white.
Muichiro's instincts flared — an unknown, terrifying presence.
Gyomei's prayer beads trembled.
Giyu watched silently, reading Jinwoo without emotion.
Even without breathing techniques, they could all feel it.
This man… is stronger than most Upper Moons.
Kagaya Ubuyashiki — the Master — smiled gently.
"Welcome, Sung Jinwoo-dono."
Jinwoo bowed respectfully.
"Thank you for receiving me."
Sanemi exploded immediately, slamming a fist against the floor.
"Master, why is an outsider sitting among us?! We don't even know if he's human!"
Shinobu responded sharply but calm.
"If he wished to harm us, Sanemi-san, we would not be standing here."
Mitsuri nodded, pink hair trembling.
"He saved me! He protected the entire village!"
Obanai's voice cut in, cold and venomous.
"And perhaps that was to gain our trust."
Jinwoo's gaze locked onto him — not angry, just indifferent.
"If I wanted you dead, I wouldn't be explaining myself."
Silence crushed the room.
Even Sanemi blinked.
It wasn't arrogance — it was certainty.
Gyomei spoke through tears of intensity, palms pressed together.
"…This warrior is burdened. He has walked through suffering deeper than hell."
Muichiro murmured, head tilted.
"The air around him feels like… a storm."
Kagaya finally spoke, calm washing the room.
"Jinwoo-dono has already confronted Muzan."
Every Hashira froze.
Gyomei's beads tightened.
Sanemi's eyes widened.
Obanai's breath stopped.
Even Giyu looked shaken.
Jinwoo continued quietly.
"Muzan came for Nezuko. He wants her power — the power to walk under the sun."
Shock rippled through the room.
Sanemi stood abruptly. "That monster is going after a child now?!"
Giyu, for once emotional, stepped forward.
"Nezuko is not a threat. I'll protect her even if the Corps opposes me."
Old hostility flared — but Kagaya raised his hand.
"Our top priority is protecting Nezuko."
Then — he turned to Jinwoo.
"Sung Jinwoo-dono, your power is unlike anything we have seen. If Muzan returns — you may be the deciding factor between our victory… and extinction."
Jinwoo said nothing.
No pride.
No excitement.
Just acceptance of responsibility.
Kagaya continued.
"So I ask you… will you train with the Hashira? And will you teach the Demon Slayer Corps what you know?"
Every voice in the room overlapped.
Sanemi: "You're asking US to teach HIM?!"
Obanai: "Unbelievable."
Muichiro: "Interesting."
Gyomei: "If it strengthens him, I accept."
Giyu: "We need him."
Mitsuri: "I support it."
Shinobu: "…necessary."
Jinwoo answered without hesitation.
"I'll do anything to get stronger."
Gasps.
Not pride… determination.
"I need strength to fulfill my mission."
Kagaya smiled warmly.
"Then we will train together. The Hashira Training will include you."
A ripple of tension spread, but no one objected after the Master's decree.
Kagaya wasn't finished.
"After the training, we must relocate Nezuko to ensure Muzan cannot reach her. She will rotate between three former Hashira households:"
He listed them slowly.
"— The former Water Hashira
— The former Sound Hashira
— And… the former Flame Hashira. Shinjuro Rengoku."
Jinwoo froze.
Rengoku.
Memories flashed — Jin-Ah yelling and crying at the TV watching mugen train movie:
"FLAME HASHIRA BEST BOY NOOOO!"
He didn't understand then.
He might now.
Why does fate keep leading me to worlds my sister cherished?
Kagaya finished softly.
"To protect Nezuko during relocation… I assign Sung Jinwoo-dono as guardian."
The hall erupted.
Sanemi: "He isn't a Hashira — that's too much!"
Obanai: "You'd entrust Mitsuri's safety to HIM?!"
Muichiro: "He's strong. It's fine."
Gyomei: "If the Master wills it, I obey."
Shinobu: "A big responsibility… fitting for him."
Mitsuri: "I believe in Jinwoo-san!"
Giyu: "He is the right choice."
Jinwoo lifted a hand.
"I don't care about position or titles. Just give me something to kill if Muzan comes."
The room fell silent.
This wasn't ambition.
This was resolve.
Kagaya bowed his head slightly — shocking everyone.
"We are grateful, Jinwoo-dono."
Jinwoo looked away, uncomfortable — not used to being respected.
The meeting concluded — but each Hashira approached him afterward:
Sanemi smirked sharply.
"Don't die during training, pretty-boy."
Jinwoo smirked back.
"Don't cry when you lose."
Lightning crackled between them.
Giyu stood quietly at his side.
"If you want to learn Water Breathing… I'll teach you."
Obanai crossed his arms.
"Don't make Mitsuri cry. That's your only warning."
Mitsuri panicked.
"Obanai, stop!! It's not like that!!"
Shinobu giggled behind her fan.
"We'll see how long you survive boot camp."
Muichiro poked Jinwoo's chest once.
"…Dense. Heavy. Not normal. I want to study you."
Jinwoo: "Please don't."
Gyomei gently placed a hand on his shoulder.
"May the gods not abandon you to darkness."
…This group was exhausting.
Jinwoo walked toward the exit — when Kagaya called softly:
"Jinwoo-dono… please protect Nezuko. She suffers the same curse you do — the burden of fate on a child."
Jinwoo's eyes glowed faint purple.
"You have my word."