The Thirteen Kings are a faction led by Femt. Despite its name, there are also female members as well, such as Aligura. Each member has a title associated with a characteristic vice.
Femt - King of Depravity
Aligura - Queen of Monomania
Zeodra The Heretic
Theodora - Queen of Hypersensitivity
King of Despair - King of Despair (Anime Only)