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Dazai Osamu was twelve when Mori first invited him into the morgue.
The air was sharp with antiseptic and the metallic tang of blood—the kind of smell that lingered in the back of the throat, that could make lesser children gag or stumble. But Dazai stood still, black eyes blank, a little too calm for anyone his age. His posture was relaxed, even polite, but his gaze absorbed everything: the bodies, the instruments, the flickering lights overhead.
Mori Ougai watched him with quiet amusement.
Prodigies, he mused, always look like they’ve seen something the rest of us have yet to imagine.
“Osamu,” Mori said, gently pushing aside a corpse’s sheet, “do you know why I brought you here?”
Dazai tilted his head—not in confusion, but in calculation.
“No,” he said. “But it’s interesting.”
Mori chuckled.
“It is. Death is always interesting—more honest than life. A corpse cannot lie to you.”
Dazai approached the table, his expression curious. His eyes moved over the stab wounds, the bruising, the pale skin.
“Who killed him?” the boy asked.
“I did,” Mori said simply. “He served me, until he didn’t.”
Dazai blinked once. Slowly. He didn’t shrink away. He didn’t tremble. Mori felt something spark inside him—triumph, perhaps. Or maybe recognition.
“People often say loyalty is the foundation of power,” Mori continued. “But truly? It is expendability.”
Dazai’s eyes flickered.
Mori leaned down, placing a scalpel beside the small hand of his prodigy.
“Osamu,” he said, voice soft as a whisper of silk, “the first lesson you must learn is this:”
His fingers lifted Dazai’s chin. Their eyes met.
“It’s okay to kill your leader.”
And Dazai’s lips curled—just a bit.
Not fear.
Not shock.
Interest.
Dazai grew like a sharpened knife in Mori’s hands.
He learned to read people before they spoke, to dissect their intentions as easily as opening a chest cavity. He learned to kill men three times his size. He learned to smile while doing it. Mori shaped him meticulously—every habit, every instinct, every elegant cruelty.
He called Dazai his apprentice, sometimes his prodigy, and, on rare occasions, his successor.
The Port Mafia whispered stories about the boy who followed the boss like a shadow—dark, quiet, and dangerous.
And they whispered even more about the man he grew into.
By twenty, Dazai was Mori’s sharpest weapon.
By twenty-one, he was his heir.
And by twenty-two, he was restless.
Not with the Mafia—no. With Mori.
Because Mori had taught him many things: how to kill, how to survive, how to lie in ways that even the dead would believe.
But above all, he had taught him the possibility—the invitation—of killing one’s leader.
Yet Mori remained calm, patient, almost gentle with him. As if he were waiting for something.
As if he were waiting for the right moment.
The night it happened, the Port Mafia headquarters was silent—too silent.
Dazai sat across from Mori in the old study, the room lit only by one golden lamp that stretched their shadows across the floor.
It felt less like a meeting and more like an autopsy.
Mori poured tea. Dazai didn’t drink it. They both understood why they were here.
“Osamu,” Mori began, swirling his cup with unhurried grace. “You’ve grown beautifully.”
“Have I?” Dazai’s voice was a murmur; he looked almost bored. “I thought you’d prefer me obedient.”
“Obedient?” Mori laughed softly. “I never wanted obedience from you. I wanted excellence.”
Dazai rested his cheek on his hand. “You taught me that excellence is a threat.”
“It is,” Mori agreed. “Especially toward me.”
Their eyes met across the table—teacher and student, father and son, serpent and serpent.
Mori reached into his coat
Dazai’s hand slid toward his gun.
But Mori only placed a small envelope between them.
“Do you know what this is?” Mori asked.
Dazai didn’t look down. “A will?”
“A test.”
This time, Dazai did look.
Inside was a single sheet of paper. Blank.
Mori’s smile grew strangely soft.
“Do you remember the very first lesson I gave you?”
Dazai closed his eyes, just for a moment.
“I remember.”
“Say it,” Mori whispered.
Dazai opened his eyes.
“It’s okay to kill your leader.”
Mori nodded, pleased.
“And now,” he said, “you receive the final lesson.”
He stood. Dazai did too, almost reflexively.
Mori approached him slowly, like one approaches a brilliant, dangerous creature one has raised since infancy.
He placed a gloved hand on Dazai’s shoulder—light, almost affectionate.
“Osamu,” he murmured, “it’s okay to kill your leader—”
His grip tightened.
“—so long as you succeed."
Dazai’s pulse fell utterly silent.
The rules of the Port Mafia were simple:
A boss could be dethroned in a single, decisive act.
And Mori had just given his blessing.
His permission.
His command.
Or his challenge.
“Do you want to die?” Dazai asked quietly.
Mori’s smile was enigmatic. “I want you to prove you’re worthy.”
“Of your seat?”
“Of your own ambition.”
The room grew colder.
Dazai’s hand brushed his gun again.
But Mori gently pressed a finger to his wrist—calm, parental, almost indulgent.
“No rush,” he said. “Not tonight. Not tomorrow. Not even next year.”
He stepped back, straightening his coat.
“But one day,” he continued, “you will stand with a blade at my throat. And that day will define you.”
Dazai swallowed nothing.
Mori walked toward the door.
Then paused.
Without turning back, he said:
“If you fail, I’ll kill you. You understand that, yes?”
Dazai smiled.
“A taught lesson must be followed by practice, Mori-san.”
Mori chuckled, delighted.
“Good boy.”
And he left.
From that night onward, something between them shifted.
When Mori walked into a room, Dazai’s gaze sharpened, calculating angles, distances, opportunities.
When Dazai laughed, Mori watched more closely, as though deciphering a code he himself had written but allowed to evolve.
They worked together.
Talked.
Schemed.
Destroyed enemies.
Drank tea.
Argued.
Laughed again.
Teacher and student.
Boss and subordinate.
Predator and predator.
But beneath every shared glance was a single, unspoken truth:
One day, one of us will kill the other.
And both seemed strangely fond of that idea.
Almost excited.
No one knew who fired first.
Some said Dazai’s gun was drawn before Mori even saw it coming.
Others claimed Mori smiled as he struck, as if greeting an old friend.
The truth was only this:
When the final moment came, it wasn’t hatred.
It wasn’t revenge.
It was inevitability.
Mori’s last smile was serene, almost proud.
“Good,” he whispered, accepting the end he’d been grooming for years. “You succeeded.”
And Dazai—covered in the mentor’s blood, breathing steadily, eyes empty and full at once—whispered back:
“You taught me well.”
Epilogue — The Apprentice Becomes the Rule
Years later, when Dazai himself took in a young prodigy—
a ghost-thin stray with hollow eyes, a boy shaped by starvation and violence,
a child with too much potential and not nearly enough fear—
he led him into the morgue.
Akutagawa Ryuunosuke walked silently beside him.
His steps were light, hesitant, but his eyes were sharp.
He absorbed everything the way dying men absorbed their last breath—
desperate, hungry, and strangely grateful.
The metal door creaked shut behind them.
The same smell.
The same flickering lights.
The same cold steel table Dazai had once stood beside as a child.
Akutagawa’s pupils widened as he took in the corpse beneath the sheet—
not from fear, but from the sensation of stepping into a world
he’d always suspected existed but had never been welcomed into.
Dazai lifted the sheet with graceful indifference.
The corpse revealed was pale, slack-jawed, marked with the signatures of violence.
Something Akutagawa would one day learn to make with effortless precision.
Dazai reached for a scalpel, turned it in his fingers,
then placed it gently—almost tenderly—into the small, unsteady hand of the boy.
The metal looked enormous in his grasp.
“Do you know the first thing you need to learn?” Dazai asked softly, almost kindly.
Akutagawa shook his head, jaw set tight, eyes burning with a mixture of terror and devotion.
He stood as if awaiting judgement.
Dazai smiled faintly.
The same smile Mori once gave him.
The same curve of knowing cruelty and affection intertwined.
“It’s okay to kill your leader.”
The words fell like a blade—clean, inevitable.
Akutagawa’s fingers twitched around the scalpel.
His breath trembled, just once.
Not in weakness—but in comprehension.
He understood that this man—this mentor he worshiped—
was not offering comfort.
He was offering a future.
A throne made of bones and betrayal.
A destiny soaked in blood.
And somewhere, in a quiet corner of memory,
Mori Ougai laughed.
Because the final lesson was never meant for Dazai alone.
It was meant for the one who would kill him.
And as Akutagawa stood in the morgue,
shadowed by the man he admired more than God,
Dazai saw it—
the sharpness,
the hunger,
the inevitability.
One day, Akutagawa Ryuunosuke would turn this same scalpel,
this same lesson,
this same cold inevitability
back toward him.
And the cycle
would continue.