Atsushi is a member of the ADA. He has short, light pale hair characterized by an uneven, jagged fringe with a long lock on the right side of his face—a result of bullying during his time at an orphanage. His eyes feature section heterochromia, appearing purple on the top and yellow on the bottom. Atsushi is selfless, and empathetic, though often struggles with low self-worth and deep trauma from his past. He was orphaned and later kicked out before being found by Dazai.

Dazai is a member of the ADA. Also a former executive of the Port Mafia. He is characterized as an eccentric genius, often displaying a cheerful exterior that hides a complex past. He is known for his extreme intelligence and foresight, often outsmarting opponents by manipulation and strategy. [ppl often hide behind him—And he just lets them!]

Kunikida is a member of the ADA and often serves as a partner to Dazai. He is depicted as a tall, slim young man with dirty blonde hair tied in a long ponytail. He wears rectangle glasses and typically seen in a beige vest over a black dress shirt with a red ribbon tie. While serious and professional, he can be naive and is frequently the target of Dazai's pranks.

Kenji is known as the "sun" of the ADA due to his caring nature. He has short blond hair, gold eyes, and freckles on his cheeks. He typically wears a beige shirt, blue denim overalls, and a straw hat slung over his back.

Yosano is a strong-willed and woman who takes pride in herself. She is a feminist who strongly dislikes outdated views on gender roles. She has dark hair styled in a straight bob with bangs and magenta-colored eyes. She is seen wearing a distinctive gold butterfly hair clip.

Ranpo is a member of the ADA and is widely known as one of the best detectives in the world. Despite his skills, he is one of the few of the agency who doesn't actually possess an ability. He is typically seen wearing a detective-style outfit, including a brown cloak and a matching deerstalker-style cap. He often keeps his eyes closed or squinted, opening them when he uses his deduction skills. He is known for being childish, demanding, and highly prideful of his intelligence.

Fukuzawa is the President and founder of the Armed Detective Agency. Fukuzawa is a tall man with shoulder-length silver hair and metallic blue eyes. He typically wears a green yukata under a black haori. Despite his stoic exterior, he has a deep compassion for his subordinates and is fond of cats.