Dolores Jane Umbridge
"I should have made my meaning plainer," said Professor McGonagall, turning at last to look Umbridge directly in the eyes. "He has achieved high marks in all Defense Against the Dark Arts tests set by a competent teacher."
Book/ Year: Order of the Phoenix/ Year 5
Distinguishing Features: Looks like a toad and wears a little black bow in her curly hair which Harry always thinks looks like a fly ready to be caught by her tongue.
Reason for Leaving: After being tricked by Hermione and Harry into following them into the Forbidden Forest, she's carried off by the angry herd of centaurs.