— A𝘯gꪮ Sakaguᥴhi.

Curiosities
The real-life Ango Sakaguchi's birth name is Heigo Sakaguchi (坂口 炳五).

His weakness is that he can keep his emotions to himself and be as insensitive as he needs to be for undercover work.

His ideal type is an intelligent woman.

His favorite food is eel.

The food he doesn't like is sea cucumber.

How he felt about his position as a triple agent: "There was no one else who could do it, so I had no choice."

Background
Not much is known about his past, but it is revealed in the second light novel, Osamu Dazai and the Dark Age, that Ango once worked as an intelligence agent for the Port Mafia, but was under orders from the government to spy on the mafia's activities. During his time working as an intelligence agent for the Port Mafia, he also became a Mimic agent under the orders of Mori Ougai.

It was later believed that Ango is not a mere government worker, but the leader of The Seventh Agency, as quoted by Mushitaro Oguri, which Ango denied when questioned, saying it was a lie told by Fyodor Dostoyevsky.

Ability
The Speech of Decay ( 堕落論, Daraku-ron) is an ability that allows the user to read the memories left behind in things, a memory extraction ability.

Despite being useful, this ability can cause considerable mental strain if the user has already grown accustomed to it. Ango confirmed that this had happened in the past when his brain temporarily surrendered consciousness to sort through a large amount of information gleaned from his ability. This ability can also work on humans, as seen when Ango volunteered to read the information sent by Sigma to Atsushi Nakajima to determine Kamui's location.

Calm, serene, moderate, perfectionist, impatient, disciplined.

Personality
For the most part, Ango is a calm and collected young man, showing more restraint than Osamu Dazai and more discipline than Oda Sakunosuke. Though he values ​​both of them as genuine friends, he firmly believes that Dazai needs someone to keep him from acting out as much as he does.

Despite being a spy for the Unusual Powers Special Division, Ango takes his role as an informant seriously. This includes his efforts to record the lives of deceased mobsters following the Dragon's Head Conflict incident. He records everything from their backgrounds to their family lives, and makes sure all close relatives are aware of their deaths, but is careful not to reveal his connections to the Port Mafia. As such, Ango values ​​life greatly.

When his true intentions are revealed at Bar Lupin, Ango struggles to remedy the tension that arises between him and the other two. However, after being shut down by Dazai and Oda, Ango respectfully leaves.

Even after the fallout, Ango continues to respect Dazai, though he seems even more exhausted than ever by Dazai's theatrical and conniving ways.

Appearance:
He is a tall man with short, dark hair, his bangs cut so that his eyebrows are usually visible, and light-colored eyes behind round-framed glasses. His most noticeable feature is a mole above his lip on the left side of his face.

His usual attire consists of a light brown double-breasted coat buttoned on the left, covering a tab-collared shirt and a kobicha brown tie. His trousers are the same color as his coat, and his shoes are approximately the same color as his.