A Ballad of Ash and Sorrow

Years after leaving the Port Mafia, Dazai is now a senior detective at the Armed Detective Agency. When a string of mysterious disappearances tied to a new underground organization begins threatening Yokohama, the ADA is forced into an uneasy alliance with the Port Mafia. And Chuuya Nakahara, his former partner and most persistent rival, is assigned to work directly with Dazai.

What begins as mutual disdain gradually shifts into reluctant cooperation, buried vulnerability, and unspoken longing - as both confront what they never said during the days they were partners in crime.

But ghosts from their pasts refuse to stay dead, and as the mission unfolds, so does the truth about a secret that Dazai has kept hidden - one that could destroy them both.

(The fanfic doesn't follow the anime storyline, so there won't be any spoilers, some enemy organizations and people I made up myself, everything else belongs to the original authors Kafka Asagiri and Sango Harukawa.)