The Port Mafia is the main antagonist organization in Bungou Stray Dogs, run by Ougai Mori. They are comprised of a large cast of recurring villains. The mafia is a mysterious organization despite at least three hero characters having a past with the organization. Although many of the members are wanted men, the general police force doesn't actively hunt them because of their power. They also have an Ability Business Permit that lets them perform some villainous operations in a legal way.
The Port Mafia is run by Ougai Mori, but he divides his power between the executives. There are at least three sub-factions that consist of the guerrilla squad, Black Lizard (Assassins), and the intelligence unit. The intelligence unit's current status is unknown since Ango Sakaguchi defected. The guerrilla attack squad has control over the Black Lizard.
The Black Lizard is known as the most brutal of the Port Mafia factions. They are a small assassination group with only one powered member, the leader. They are a sub faction of the Guerrilla Attack Force.