Watch Teenage Exorcist for Free: How to Stream the Movie Online at 123Movies. . Diane is a repressed, neurotic grad student, who moves into a cursed mansion only to be possessed by the house's demonic master. She is then transformed into a raven-haired, leather and lingerie-clad seductress, who seeks a virgin sacrifice for her master. Meanwhile her sister, brother-in-law, a priest, and a pizza boy try to rescue her while avoiding the demon's wrath.