Best audience reaction
Okay, so the film is vaguely related to "Cat People" (1982) in that two of the main characters are an incestuous pair of werecats, although, in this case, it's mother-son and not brother-sister.
When I went to see the show, the film got to the point where the incestuous angle began to play out on screen and the son was tonguing mom's tonsils. All of a sudden, someone out in the theatre suddenly let out with a loud "Mommy... mommy.. I WANT my mommmy!"
Horror film or not, the entire theatre audience just about killed themselves laughing for a good three minutes.