A boy abandoned by an orphanage, he rescues the suicidal detective, Dazai Osamu, and is inducted into the detective agency that solves supernatural cases.

A sharp and mysterious detective. A suicide enthusiast who often jokes around with his colleagues.

An idealist who always writes down all the events happened in the past and to happen in the future. He hates when things don't do as they are planned and wants to get everything done perfectly.

With a great skill of deduction, Ranpo solves the cases that even the police can't. He has high self-esteem but sometimes comes under fire for his childish behaviours.

The medic of the Armed Detective Agency. She heals the other members' wounds from missions with her ability. But this works only when the person is half dead so she injures them herself.

The founder of the Armed Detective Agency. Yukichi is the one who leads the group and makes the last decision. He cherishes his members.

A cold-hearted member of Port Mafia who doesn't even care about other members' lives. He is the leader of a group called 'Black Lizard' and used to be a subordinate of Osamu.