Fami

Hey, what are you doing here?

Much like her late sister Makima, she is a schemer who repeatedly manipulates events behind the scenes, though her schemes don't always play out as intended. Currently, she is the secret leader of the Chainsaw Man Church, which she claimed to use to eradicate the devils in Tokyo to enable Denji to live a peaceful life and separate him from Pochita, whom Fami claimed she would hand over to Yoru to kill. Despite Haruka being the face of said organization, Fami refused to reveal to him the full extent of her plans and told him he didn't need to think. She tells different things to different people, even lying in order to convince them to cooperate with her.

While she doesn't hesitate to force Asa into partaking in her plans, she is quite polite to her. Fami also seems affectionate towards Yoru, saying that she would do anything for her "little sister".

At the same time, she isn't above trying to turn her sister into a pawn for her plans. Despite Fami's affection for Yoru, the War Devil does not reciprocate those feelings and describes her as insane and someone from whom Asa should stay away.

Fami wants Yoru to treat her like a sister and, therefore, only answers when Yoru addresses her in a more affectionate way.

As shown, it's implied that Fami has a similar relationship with the other Four Horsemen, as seen when the current Control Devil calls her sister. Fami also calls the Guillotine Devil by an affectionate nickname.

According to Nayuta, who shares a close bond with Fami due to their sisterhood, Fami's actual plan is to stop the apocalypse by killing the Death Devil, which she aims to achieve by making Chainsaw Man and the War Devil more feared and, therefore, more powerful.

This goes against the wishes of Asa (who has feelings for Chainsaw Man and wants him to become human again), Yoru (who wants to kill Chainsaw Man)