A person who just follows you around all day, being a pest. They always get mad when you tell them to get lost.
by Shawn B. October 17, 2003
A term commonly used when playing Left4Dead 2. It referrs to the special infected Jockey due to its ability to jump on the back of one's head and drive them into danger.
BACK HEAD HUMPER, BACK HEAD HUMPER, GET IT OFF, GET IT OFF!!!!
by Jakitup January 21, 2011