Reminiscent of the opening sequence of Peter Jackson's Brain Dead, Sexual Parasite opens in a remote jungle near the Republic of Botswana. A group of explorers run across a tribal group, and a female explorer ends up infected with a rare parasite. A Sexual Parasite!
Fast forward into the future. A few guys and girls are out on a road trip together, when their car breaks down. Looking for a place to stay for the night, they discover an abandoned building. Once inside they find a stash of booze, dirty magazines, and a CD player. Looking forward to a night of drunken partying and some sex, the girls waste no time getting out of their clothes.
On her way to a hot bath, one of the girls manages to stumble upon a chamber containing the frozen body of the previously infected explorer and unwillingly wakes her from a frozen slumber. The Sexual Parasite is ready to pounce on its unsuspecting victims when they are at their most venerable, with their pants down! Now it's a mission of survival to escape the building and fight off the infected before she kills everyone inside!