A Vizier or Grand Vizier is an Arabic term for a high-ranking religious and political advisor, often to a king or sultan. During the days of the Ottoman Empire the Grand Vizier played the role of a pseudo-prime minister in the Emperor's court.
In comtemporary literature the "Grand Vizier" is a character stereotype and is usually portrayed as a scheming backroom plotter and the clear power behind the throne of a usually bumbling or incompetent monarch. The best example of this is the sinister character of Jafar in the Disney movie Aladdin who plots to take over the entire Kingdom of Agraba under the nose of the nation's juvenile and stupid sultan.
Throughout history the notion of the sinister Grand Vizier has often been evoked when a political leader appears to be developing a cozy relationship with a spirtual advisor of questionable scruples or talents.