Joanna "Jo" Harvelle is a hunter of supernatural creatures with over 10 years of experience and an ally of the Winchester brothers, Dean and Sam. She specializes in the use of weapons and explosives, enjoys rock music, and is non-religious. She also has mob ties and contacts with groups of assassins and vigilantes who she says are wronged by society. Her favorite color is black, and she cannot stand alcohol, having lost her mother and father to alcoholism.