Madame Kovarian (originally known as Eye Patch Lady, arrrrr!) was an epic meme who hung out with The Silence. She kidnapped Amy and turned River Schlong into a deadly assassin to kill the Eleventh Doctor.
After watching the Siege of Trenzalore drag on for fucking centuries Kovarian got fed up and decided to travel back in time and engineer a perfect psychopath to kill the Doctor so she could get back to Baneposting on 4chan. Unfortunately for her The Power of Love was just too powerful.
Appeared in Day of the Moon, The Curse of the Black Spot, The Rebel Flesh / The Almost People and Closing Time but was mostly featured in A Good Man Goes to War and The Wedding of River Song. Also appearing in Big Finish.