"You're going to leave just like that?" Chuuya's voice rises, his eyebrows furrowing as he glares at his partner.

"Yes," Dazai says with his legs crossed.

Chuuya has no idea why Dazai thought it would be a good idea to tell him that he was leaving the Port Mafia for good; maybe it was to spite Chuuya, knowing the fact that he won't be able to leak the real reason why Dazai left due to his trust in his partner.

"You're going to leave Kouyou and Mori and Hirotsu and your other colleagues just because your friend died?!" Chuuya fumes.

Dazai casts his eyes downward. "They're already dead to me."

Chuuya's hands clench into fists, rage bubbling beneath his skin.

"They were the ones who took you in, who became your family! And you're going to leave them for your own selfish desires?!"

"Yes."

Chuuya grits his teeth as he raises his fist and swings it into Dazai's cheek, making the man jolt backward, his head snapping to the side.

"It's always yes, yes, yes! Can't you say something other than that you piece of shit?!"

Dazai's cheek is red, but he stays silent, his head tilted to the side.

"Say something you bastard! You-"

"I'm leaving tonight," Dazai drawls out his words.

Chuuya's heart leaps into his throat, and his breath stops short.

"Tonight?"

"Yes."

Chuuya swallows thickly, and his breaths become labored as he takes deeper breaths.

He doesn't want Dazai to leave. He doesn't want to lose the only person he can rely on. He doesn't want Dazai to fucking leave him behind as that selfish bastard turns a new page in his life while Chuuya's stuck in between the lines of his own.

His eyes catch Dazai's for a split second, and then he knows. He knows that Dazai's not lying, that he will be gone the next morning, vanished without a trace and only Chuuya will have known where he'd gone.

"You're really leaving tonight then..." he wills his voice steady, unclenching and clenching his fists.

"Yes."

"Then I'm already dead to you, aren't I?"

"Yes."

He's expected the answer to be yes, but he isn't prepared for the emotional blow that hits him in the chest like a wrecking ball.

"Leave." Chuuya points to the door, his eyes narrowed into slits. "LEAVE!"

Dazai gets up without a sound, picking up his jacket discarded on the floor before he shuts the door behind him with a click.

He doesn't even say goodbye.

~

Dazai's come back.

Mori's offered the role of Mafia Executive, and to everyone's surprise, he accepted without a word.

Chuuya knows it's too good to be true. Dazai would never leave something he was dedicated to, nor turn his back on it.

He should be overjoyed, euphoric even at the least when Mori tells him that his partner had secured a position in the Port Mafia again and that Double Black will be reunited.

It may be true that he's had feelings for Dazai even before his partner had left the Mafia, but Chuuya can't suppress the rage boiling in his veins.

So when Dazai comes back to his - their - apartment that night, Chuuya greets him with a hand around his neck.

"Someone's excited to see me," Dazai chortles, and even that sends Chuuya's heart fluttering like a damned butterfly.

"You fucker," Chuuya snarls as his knee slams into Dazai's gut, earning a sharp gasp from the man. "Leaving the Port Mafia for four years and then deciding to return when Mori offers you your position again?! Son of a bitch!"

He swings his fist into Dazai's cheek, the familiar feeling of his knuckles against Dazai's face fueling his anger.

"FIGHT ME!" Chuuya spits, kicking Dazai in the stomach, sending him doubling over. "OR ARE YOU TOO MUCH OF A COWARD TO DO SO?!"

Dazai stays silent, though his smirk has long gone from his face.

"I thought so," Chuuya turns around, flexing his gloved fingers.

Just as he's about to leave, Dazai grabs him by the arm and the waist and pulls him in.

A pair of warm lips smash against his own, and Chuuya can feel his breath being taken away by Dazai.

He's longed for this feeling again during those four years that Dazai's left. He's longed for Dazai's touches, his kisses, his teasing. He's longed for company.

"There," Dazai breaths as they part. "I punched you on the lips with my lips," he grins like a maniac.

Chuuya flushes, gritting his teeth. "You bastard-!"

Dazai pulls him in then, closer to his chest as his taller body wraps around Chuuya like a blanket.

"Wha-?!"

"I'm staying, for real," Dazai murmurs against Chuuya's hair.

"I find that hard to believe."

"It's the truth."

Chuuya stays silent, allowing himself to relax in Dazai's hold. He inhales the scent he's missed for far too long, his hands clutching at Dazai's shirt.

"You're really staying then?" He says softly, hoping that Dazai isn't pulling some sort of prank.

"Yes."

There's another flutter in Chuuya's chest as his doubts disappear from his mind.

Maybe he will no longer be lonely.

~

It's been several months since Dazai's been back, and the Mafia's been more successful than ever.

But, there's something wrong with Dazai and Chuuya seems like the only one who knows about it.

He can't prove his assumptions, however, for Dazai's been sealing Chuuya's lips with his own every day, keeping him silent. Dazai's occupied all of Chuuya's free time worshipping him, murmuring praises against his ear as Chuuya loses himself over and over again.

Chuuya has barely enough time to get to work in the mornings, let alone meet up with Kouyou to express his concerns.

He knows that Dazai's been sneaking off every night going to who knows where.

He knows that Dazai's been overthinking things with the way that he talks and walks; there's clearly something troubling him, but Chuuya doesn't know what.

He knows that Dazai's been less suicidal and flirtatious these days, unlike his past personality.

He knows...

He knows that Dazai doesn't genuinely love him, even if Chuuya does return those feelings.

All of those moments they have together, at night and during the day, all seem forced and Chuuya can tell.

His heart's slowly breaking apart, and it's all because of Dazai fucking Osamu.

~

The day that Chuuya's world crumbles around him is the day that Mori dies.

It had been unexpected, his death. Everyone was shocked; how had their boss suddenly just... die?

With his ability and knowledge of fighting, it was highly unlikely that he could have been taken down in a night.

Of course, this shakes the Mafia to the core, including Chuuya.

Dazai takes Mori's place, and no one questions him as he gives his first order of the boss of Port Mafia: burn the corpse.

Then, everything goes downhill.

Akutagawa and Gin go missing first. The siblings leave without notice, and Dazai doesn't seem bothered by it. Chuuya's confronted him, but all Dazai's done was reassure him that the Akutagawa siblings may have left by choice and that he isn't going to create a search party for them.

The rest of the Black Lizard leaves second. Dazai's apparently sent them on a mission. Chuuya finds that extremely hard to believe.

Chuuya wakes up to the Port Mafia headquarters exploding on the third day since the disappearances have started.

He rushes to the scene using his ability to leap from roof to roof.

"Dazai!" He yells as he bursts past the crime scene tape despite the yelling. "Dazai!"

Chuuya finds Kouyou first in a pile of rubble. She's bleeding from the forehead, and a steel beam protrudes from her stomach.

"Ane-san?!" Chuuya kneels over Kouyou, taking her head in the crook of his elbow. "Ane-san?! What happened?!"

Kouyou cracks open her eyes, but very slightly as she winces in pain.

"Dazai," she gasps, her breaths shallow and light.

"Dazai? Did something happen to Dazai?!"

"Dazai... explosion..." Kouyou grits her teeth as she looks down at the beam sticking through her stomach.

"Ane-san!" Chuuya's eyes widen, panic seizing his mind. "Kouyou! KOUYOU!!"

Kouyou goes limp in his arms, her head rolling to the side as her eyes close.

"KOUYOU?!"

"If you'd been here a minute earlier, you might have saved her."

Chuuya's head snaps upward, tears burning behind his eyes.

"Hello, Chuuya," Dazai's coat flutters in the breeze as he holds a book in his hand.

"Ane-san-" Chuuya pleads helplessly, cradling her head.

"She's dead, let it go," Dazai says blandly, stepping down from the rubble.

Chuuya's taken back by Dazai's answer.  "Then-"

"Every Port Mafia member is dead," Dazai says smoothly. "All except you."

"How?" is all Chuuya can muster out.

"Who do you think it was, Chuuya? You know the answer, don't you?" A smirk spreads across Dazai's face while he prompts the redhead.

"Y-you-" Chuuya stares up at Dazai, "you did this."

"Ding, ding!" Dazai chirps. "One point to chibikko!"

"Why... WHY?!" Chuuya screams, launching himself at Dazai. His body glows with a red outline as he roars with rage.

He knows For The Tainted Sorrow is useless against Dazai, for with a simple touch, Chuuya's ability is deactivated, countered by No Longer Human.

"I'm leaving tonight," Dazai says, barely above a whisper.

Chuuya collapses to his knees, his knees spread out as he stares at the ground. "You're leaving again."

"Yes."

"After all you've done; you killed everyone you've ever known, you've played with my feelings and now you're leaving?! So what?! So you can run away from your problems?!"

"I'm leaving Yokohama."

At that moment, Chuuya's feelings for Dazai - all his love, all his affection for his partner dissipates - snap in half, its edges becoming frayed like a string's split ends.

All he feels is rage, utter fury at his naivety to have believed that Dazai would never leave him again.

"WHY DON'T YOU KILL ME TOO?! END MY SUFFERING, OSAMU. END. IT." Chuuya grabs Dazai by the collar of his shirt, forcing him to meet his eyes. The use of his first name sends a shock through Dazai's eyes.

"I FUCKING DARE YOU! KILL ME AND GET THIS OVER WITH! KILL ME AND END YOUR PROBLEMS, YOU BASTARD!"

A strong urge to choke Dazai until he passes out overwhelms Chuuya to the point where he can see only white in his vision.

He remembers screaming something at his partner, yelling, screaming, hollering things until his voice turns raw. He remembers Dazai taking every blow dealt to him by Chuuya's fists, every profanity that Chuuya spits into his face.

Chuuya's chest heaves when he's finished, his grip lessening on Dazai's collar.

There's nothing he can do now. He wants Dazai to leave, to leave and get the hell out of his life.

"I'm leaving," Dazai manages to speak calmly through a bloody nose.

"Leave, then, you piece of shit." Chuuya's glare nearly sends daggers into Dazai's soul when he stares up at the man. "I don't fucking want to see you in my life ever again."

Dazai stands up and turns around, his back facing Chuuya.

"Goodbye."

Once Dazai's footsteps fade away, Chuuya breaks, his soul and heart snapping into pieces, shattering like glass on a floor. He cries for Kouyou, the mother he'd never had, the one who helped him get his shit back together when Dazai left. He cries for Mori, who's treated him like his son ever since the day he joined the Mafia.

He cries for Akutagawa and Gin and Hirotsu and Tachihara, their location undefined as if they were wiped off the face of this Earth.

Lastly, he cries for himself, cries at his stupid, abhorrent feelings, cries at the amount of trust he'd put into Dazai, cries at the way he let himself be fucked and used like a rag doll.

Once his eyes are dry and his throat sore, Chuuya sits at the center of what once was the strongest organization in Yokohama, in the middle of scattered corpses.

He's left alone again, and this time, there's no one to fix him.