In Gonna Set Your Flag On Fire, they are revealed to police and enforce their own set of rules in the Fauline asylum like regular orderlies, forcing witches to take Lobelia pills that make the witches unable to focus or concentrated in order to practice magic. It is currently unknown how they acquire these pills or how many members they have, though what is known is that they were trapped in the asylum by their own coven for using necromancy and immortality spells. All the shown members have scars on their faces.
In Sanctuary, Rebekah rebels against them and plans to escape. She lets Cassie and Freya in on her plans, however, Cassie betrays Rebekah and Freya, revealing that she was the Kindred's newest member. Freya saves her sister from the members of the Kindred by killing them, including Cassie. Rebekah and Freya then escape the asylum.
As part of an initiation rite, members are given two scars across their cheeks.
It appears that female members are given the scars on their right cheek while male members are scarred on the left.
It is currently unknown what the actual number of members or if there is anyone left alive after Freya's attack.
They do not hesitate to use violence to control the witches at the Asylum.
A number of years prior, an unspecified coven of the Nine Covens of New Orleans banished several of its members to the Dowager Fauline Cottage for obsessing over and practicing dark magic, specifically Necromancy and Immortality Spells.
Contradictory to the actions of the coven that expelled these witches, Vincent states to Davina in City Beneath The Sea that as Regent, she'd have a direct connection to the Ancestors, giving her access to various forms of magic and magical practices, including Necromancy.