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The Port Mafia reeked of iron. Of blood. Of gunpowder. Of ambition and betrayal and rot.
Akutagawa Ryuunosuke knew no different. Since the first moment his ribs broke beneath the boot of a superior, since the moment Dazai looked down at him and deemed him weak, Akutagawa had understood: the world is cruel. And the only way to survive was to become crueller still.
Dazai called him a dog. Mori called him a weapon. Most called him terrifying. And he accepted every name, every scar, every punishment, because to bend was better than to break. The streets of Yokohama were not kind to orphans. And the Port Mafia was even less forgiving.
But—
There was one thing Akutagawa could never fully lose.
One reason he kept returning alive.
One reason he swallowed blood and pride and humiliation just to stand again.
Gin.
His little sister.
She was quiet. Almost invisible. Her steps were soft; her voice even softer. To the world, Gin was just another faceless blade of the Mafia. But to Akutagawa, she was everything good left in him.
She never needed to speak for him to understand. When they were younger and starving, her tiny hand would tug at his sleeve, and he’d lie—“I already ate. You take the rest.” She’d stare at him with those large, ghostly eyes, already so wise and knowing, and never call him out. Just quietly accept the bread and break it in half to share it back.
She was the only person who looked at him and didn’t see a monster.
And for her sake, Akutagawa bore the burden of monstrosity.
He carved his place in a world of demons so that Gin would never have to kneel. Never have to grovel like he had. Never need to fight, unless she chose to.
Rashoumon was a beautiful kind of death. Elegant. Unforgiving.
Akutagawa became a legend with it. A reaper in a black coat, skeletal in form and even more so in soul.
But behind every brutal kill was a promise whispered to himself: “I will survive. For Gin.”
He let Dazai mock him. He let the world spit on him. He bore the weight of the Mafia's filth because he was strong enough to carry it—if it meant shielding Gin from it.
“She shouldn't be here,” he said once to Mori.
“And yet she is,” Mori replied, eyes glinting like scalpels. “Your sister is exceptional. Perhaps more than you.”
Akutagawa said nothing. He could not argue. Gin was exceptional. Not because she killed. Not because she obeyed orders. But because despite it all—despite the rot and ruin of the Mafia—she remained kind. Gentle.
Untouched.
An angel among wolves.
And he would murder the world to keep it that way.
But then, something tragic happened.
It was supposed to be simple.
Gin was sent on reconnaissance. Just surveillance. But the enemy—some underground group high on ideology and explosives—had planned better.
When he got the call that she was missing, Akutagawa didn’t ask permission. He didn’t wait. He stormed their hideout like a hurricane in black, ripping men limb from limb with Rashoumon’s jaws, his eyes feral.
Blood sprayed across his face. Screams echoed in the stone corridors.
He found her in a cell, her mouth bleeding, her mask ripped away, chained at the wrist and refusing to beg.
Even then—even then—her eyes softened at the sight of him.
“Ryuu,” she whispered, voice hoarse. “You came.”
And something inside him cracked.
He carried her out like a knight cradling a broken bird.
She had bruises he couldn’t erase. And yet she leaned into him like he hadn’t failed her. Like he hadn’t taken too long. Like he was still someone worthy of being her brother.
She rested her forehead against his collar and said softly, “You always come for me.”
His voice broke. “Always.”
Later, when she slept in the infirmary, Akutagawa sat beside her, watching her breathe like it was the only thing anchoring him.
He’d killed twenty-three people that day.
He’d smiled during it.
He’d become what everyone said he was: a demon in human skin.
But…
Gin was safe.
Alive.
Untouched in the ways that mattered.
And that made it worth it.
Akutagawa Ryuunosuke never believed in gods. Never in fate. Never in redemption. He believed in strength. In pain. In survival.
But when it came to Gin—
When it came to his angel—
He believed in love.
Brutal, sharp-edged love. The kind that carves through armies. The kind that lights fire to the world. The kind that shatters the spine of hell just to hold someone safe.
And if this world was filled with demons, then so be it.
He would walk through every one of them.
He would become one himself.
For his beloved sister.
For her.