That night, the Demon Slayer Corps Headquarters glowed brightly beneath the pale lantern light.
A special guest had arrived at Oyakata sama's invitation.
"Thank you for coming, Miss Tamayo."
Oyakata sama spoke gently as he looked at the woman in the floral kimono before him. His voice was weakened by illness, and he covered his mouth as another painful cough escaped.
Amane knelt at his side, her expression filled with worry.
"It is my honor," Tamayo replied softly.
She and Yushiro knelt on the tatami, facing the head of the Ubuyashiki family.
For centuries, this family had offered countless lives for one purpose, to bring down Kibutsuji Muzan.
Receiving a direct summons from Oyakata sama weighed heavily on her, yet she did not hesitate to accept.
"The reason I invited you," Oyakata sama continued, taking the handkerchief Amane handed him, "is that I hope we can join forces, so we may finally rid this world of Kibutsuji Muzan."
His next cough brought blood to the cloth.
Even so, his voice remained steady.
"I believe you already know the current situation. All nine Hashira have fallen."
He lowered his gaze, recounting the events of the last ten days.
"Two unexpected individuals have also appeared. One of them is Lucien, and the other is the former Lower Moon Five, Rui."
Tamayo's eyes narrowed slightly.
"Ten days ago, those two fought fiercely in Yoshiwara.
Rui resurfaced soon after and began hunting the remaining members of the Twelve Kizuki, while Lucien disappeared.
Their goals remain unknown, but one thing is clear.
Muzan, Rui, and Lucien are all enemies, locked in conflict with one another.
Muzan remains the greatest threat.
If he is wounded severely enough, Rui or Lucien may finish him."
He exhaled slowly.
"And if Muzan dies, Lucien and Rui will inevitably clash.
My wager is that Lucien will win.
Even though he is responsible for the deaths of several Hashira, if he kills Muzan, humanity wins."
Tamayo remained silent, her expression unreadable.
"What do you need me to do?" she asked at last.
If there was any chance to kill Muzan, she would use it.
"We must create an opening for all three of them," Oyakata sama answered quietly.
By the latter half of the night, Tamayo left the mansion, leaving behind the medicines she had spent years developing.
Meanwhile, explosives infused with Wisteria were buried throughout the courtyard, waiting for their moment.
The bait was ready.
That afternoon, another unexpected visitor arrived.
Lucien followed a Kasugai Crow through the gates, his amethyst eyes sharp and unreadable.
Oyakata sama lay on the tatami inside the open room, as though he had been waiting for this exact moment.
Lucien paused outside the room, his gaze sweeping slowly across the courtyard.
He knew this place was likely filled with Wisteria bombs.
In the original events, these traps were for Muzan, but Lucien had no way of knowing whether Oyakata sama would try to use them on him.
After discovering that Nezuko could withstand sunlight, Lucien had gone into the city to commission an airtight iron box, thirty centimeters thick.
He had picked it up only this morning.
That was when the Kasugai Crow appeared with Oyakata sama's request.
The offer intrigued him, so he came.
"Won't you come in for tea?" Oyakata sama asked, sitting cross legged with Amane's support.
"I am afraid you will blow me up," Lucien replied.
A cloud of smoke formed in his hand along with a lighter.
He lit the cigarette, inhaled calmly, then exhaled a slow stream of rings into the air.
Oyakata sama flinched slightly, then smiled with resignation.
"Although I do not know how you learned of it, the message delivered by the Kasugai Crow was true."
"Why cooperate with me?" Lucien asked, his tone lightly mocking.
"Because you are human."
Silence stretched between them before Oyakata sama continued.
"No matter what you have done, no matter whom you have killed, you are still human.
If you win, then humanity wins.
For that reason alone, I can put aside any grievances."
"How noble of you," Lucien murmured, flicking the ash from his cigarette.
"So, will you cooperate with us?"
"That depends.
Tell me you and Tamayo's plan first."
Oyakata sama paused.
Lucien's knowledge was unsettlingly precise.
The plan had been finalized only hours ago, known to only a handful.
The thought of Tamayo revealing it flickered across his mind, but he dismissed it quickly.
"As you suspected, this mansion is filled with specially crafted bombs containing Wisteria flowers.
If Muzan is lured here, these bombs will wound him severely.
In addition, Tamayo has left a medicine that inhibits a demon's ability to regenerate."
He coughed again.
Amane opened a small wooden box, revealing a glass vial filled with green liquid.
"I intend to lure Muzan here and die with him.
When that moment comes, all you must do is inject this medicine into his weakened body.
With your ability, you can restrain him until dawn or kill him entirely."
Amane stepped out into the courtyard and offered the box to Lucien.
He accepted it, staring thoughtfully at the vial.
His expression shifted, filled with the sense that fate itself had begun turning in his favor.
Oyakata sama cooperating with him had been the last thing he expected, yet it was perfectly logical.
With the Hashira gone, the Demon Slayer Corps was barely holding together.
To kill Muzan, Oyakata sama needed him.
Lucien closed the box decisively.
"Fine."
Whether the medicine would actually be used on Muzan was another matter entirely.
"The operation begins tomorrow night.
Muzan has been searching for the Ubuyashiki estate for centuries.
He will come."
Lucien left the estate soon after.
He retrieved the iron box he had hidden in the grass, took the medicine, and departed.
He needed to hide Nezuko properly.
Tomorrow night, after he devoured Muzan, he would merge Nezuko into himself instantly.
Oyakata sama was proving to be a surprisingly good ally.
This increased Lucien's chances of success more than he had anticipated.
…
Meanwhile, no one in the world was in a worse mood than Kibutsuji Muzan.
Among the Twelve Kizuki, only Douma, Nakime, and Kaigaku remained.
His rage simmered uncontrollably.
But Nakime brought him a welcome report.
The Demon Slayer Corps Headquarters had finally been located.
He wanted to vent this fury, and the Ubuyashiki family, who had defied him for generations, was the perfect target.
The night sky was bleak, thick clouds covering the moon.
The world felt draped in a dark shroud.
Inside the Ubuyashiki mansion, Oyakata sama lay on the tatami.
Amane tended to him, their daughters Hinaki and Nichika kneeling close.
Tamayo concealed herself in the shadows, waiting.
High above the estate, Lucien hovered silently in the sky, watching.
In the depth of night, a lone figure entered the grounds.
Muzan arrived in a black overcoat, suit, and tie, stepping into the courtyard with cold elegance.
His plum red eyes stared at Oyakata sama without emotion.
"You finally found your way here," Oyakata sama said calmly.
He no longer had the strength to rise.
"Amane, describe him."
"He appears to be a man between twenty five and thirty years old.
His eyes are plum red, and his pupils are narrow like a cat's," she answered softly.
"I see," Oyakata sama murmured.
Another fit of coughing shook his frail body.
"I knew you would come.
You must despise me, despise the Ubuyashiki family.
You would never miss the chance to kill me with your own hands."
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