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The first time Dazai hears it, it doesn’t feel like a haunting.
It feels like memory.
Rain presses against the windows of the Armed Detective Agency, turning Yokohama into a blurred watercolor of grey and sodium light. Inside, the office is warm, cluttered, alive in the way Dazai Osamu always finds unbearable and irresistible at the same time.
He should be working.
He is not.
Instead, he is leaning back in his chair, one leg hooked lazily over the armrest, bandaged fingers spinning a pen he isn’t really watching. Atsushi is somewhere across the room, reading a file too carefully. Kunikida is shouting about deadlines. Tanizaki is trying to disappear into the furniture again.
Normal.
Ordinary.
Safe.
And then—
“You can be good.”
Dazai’s pen slips.
It clatters onto the desk, once, twice, rolling until it stops against a stack of reports.
The office keeps moving. No one reacts.
Of course they don’t.
Because the voice didn’t come from the room.
It came from inside him.
Warm. Familiar. Impossible.
Dazai’s eyes narrow slightly, but his smile doesn’t fall. It only thins, like paper stretched too far.
“…That’s a new one,” he murmurs lightly to no one at all.
But his chest has already tightened.
Because he knows that voice.
Not as sound.
As consequence.
The second time, it’s worse.
He’s on a rooftop alone—because of course he is.
Wind cuts through Yokohama like a blade. Below, the city continues its endless pretending. Above, the sky is too open, too honest.
Dazai stands at the edge with his heels just shy of nothing.
This is familiar too.
So familiar it almost feels like home.
“You can be good.”
His breath catches—just slightly. A mistake so small no one else would ever notice it.
Dazai closes his eyes.
For a moment, the world shifts.
Not into darkness.
Into memory.
A small café. Soft light. A man with gentle eyes and ink-stained patience. A smile that never asked for anything except honesty.
Oda Sakunosuke.
Dead friend.
Dear dead friend.
The one who told him to stop choosing endings.
Dazai exhales slowly, reopening his eyes to the wind.
“You’re getting sentimental,” he says softly. “Even for a hallucination.”
But there’s no humour in it.
Not really.
Because hallucinations don’t root themselves this deep.
They don’t feel like guilt given a voice.
It becomes a pattern.
Not every day.
Not always when he expects it.
But always when he is closest to something sharp.
A gun in his hand.
A fight he could end too easily.
A moment where the world offers him violence like an old friend offering a chair.
“You can be good.”
It never changes.
Never argues.
Never demands.
Just repeats itself, as if repetition could rewrite him.
And slowly—dangerously—Dazai begins to respond.
Not aloud at first.
In thought.
In hesitation.
In the smallest fraction of mercy where there used to be none.
It frustrates him more than anything else ever has.
Because it feels like losing control to someone who is already dead.
“You’re not real,” he says once, in the quiet of his apartment.
The room doesn’t answer.
Of course it doesn’t.
But the voice does.
“You can be good.”
Dazai laughs.
It’s sharp. Almost bitter.
“Good?” he echoes. “That’s not a word you used lightly.”
Silence.
Then—
“You know what I meant.”
His smile falters.
Just for a second.
Because yes.
He does.
The real fracture comes when he meets Atsushi after a mission gone too far.
Blood that isn’t his. Rain that won’t stop. Atsushi’s hands shaking in a way he is trying very hard to hide.
Dazai watches him carefully.
Too carefully.
As always.
And then, faintly, like a hand brushing the edge of thought—
“You can be good.”
Dazai freezes.
Not outwardly.
Never outwardly.
But something inside him shifts.
Because this time, the voice doesn’t feel like memory.
It feels like instruction.
Like permission.
Like a door being nudged open from the other side.
Atsushi looks up. “Dazai-san?”
Dazai blinks once, slow.
Then smiles.
“Oh, nothing,” he says lightly. “Just thinking.”
But his gaze lingers a moment too long on Atsushi’s still-trembling hands.
And for the first time in a long time—
he does not immediately calculate how to break someone.
He calculates how not to.
Later, Chuuya notices.
He always does.
“You’re off,” says Chuuya Nakahara bluntly, narrowing his eyes across a bar table.
Dazai tilts his head. “Off? That’s rude. I prefer ‘mysteriously improved.’”
“Don’t joke,” Chuuya snaps. Then hesitates. “You’re hesitating more.”
That lands closer than it should.
Dazai’s fingers pause around his glass.
For a fraction of a second too long.
“You can be good.”
The voice again.
Soft.
Unrelenting.
Chuuya’s expression sharpens. “Who the hell are you talking to?”
Dazai smiles, but it’s thinner now. Controlled in a way that feels almost fragile.
“No one,” he says.
And for once, Chuuya doesn’t believe him.
It reaches its breaking point on a night soaked in danger.
A target. A weapon. A decision that would be easier if Dazai were still who he used to be.
Everything is in place.
Everything is simple.
Everything is waiting for him to choose what he has always chosen.
And then—
“You can be good.”
Dazai stops.
Really stops.
The wind is loud. The world is loud. His thoughts are loud.
But that voice cuts through everything like something unbearably gentle.
Not commanding.
Not accusing.
Just… certain.
And suddenly, Dazai understands something he has been avoiding for years.
The voice isn’t trying to change him.
It is reminding him of something he already knows.
Something Oda never stopped believing.
Not as a ghost.
Not as a hallucination.
But as the shape of a promise Dazai made and never fully broke.
His hand lowers slightly.
Just a fraction.
Enough.
The mission does not go as planned after that.
Not in the way it would have.
Not in the way it used to.
And for the first time, that feels less like failure—
and more like choice.
Later, alone again, Dazai stands by the river.
The water moves like it has nowhere to be, which he has always envied.
“You’re annoying,” he says softly into the air.
A pause.
Then, quieter:
“…But I heard you.”
The voice does not answer.
It doesn’t need to.
Because for once, it has already done what it came to do.
And in the silence that follows, Dazai Osamu allows himself something dangerously close to change.