Mike Whitehead
Ultimate Fighter and one time UFC veteran Mike Whitehead is quite possibly the most disgusting person on this list. He certainly had a reputation of being a mid-level opponent as a pro fighter, but he truly is a top level scumbag/pervert outside the cage.
He was arrested and charged for a 2012 double sexual molestation, which included the rape and assault of a woman as she slept, right in front of her friend no less.
Whitehead was sentenced to one to four years in prison, later getting released in 2015.