Missy

Doctor Who
Missy, which is used as a short-form for mistress, is the female iteration of the regenerating renegade Time Lord known as the Master. Missy comports herself as something like an evil Mary Poppins. Though she is a constant foil to the Twelfth Doctor, she also holds him in strong regard, and considers him her oldest friend. Oh, and she's completely nuts too. She'll tell you herself. She's bananas.