Audience-Alienating Premise: If you're pro-chastity and like your entertainment to be family friendly with wholesome morals in general, watching Dawn get sexually corrupted by her foul-mouthed misbehaving peers is likely to make this movie a revolting experience for you. If, on the other hand, you're into sleaze and skin flicks or just like stories in which Everyone Has Lots of Sex in general, you probably aren't going to enjoy watching guys getting their penises bitten off. Feminists won't much enjoy the Lifetime Movie of the Week feel of the movie, and the kind of women who do like Lifetime movies still aren't likely to enjoy the graphic violence and gore. Basically, any Target Audience this movie might have (save for a hyper-specific group of feminist horror fans who can look past some of the problematic parts) is not going to like certain aspects, with the exception of horror comedy junkies who can jive with the premise (and, frankly, since horror comedies are so far and few between, they might give it a shot regardless).
While far from a knock on the film's quality (it did incredibly well at Sundance), the subject matter and themes are so bizarre as to warrant this response from mainstream audiences.
Narm Charm is also a possibility, and any Rape and Revenge afficionado who's in a hurry to get to the "revenge" part might like to see this. Narm Charm is especially invoked in the 20 minute lead-up to the first *ahem* amputated appendage, which is more akin to a Cringe Comedy, playing almost like a Tim and Eric sketch about pro-chastity teenager tropes in film.
Critical Dissonance: The film was well-received by critics but was met with a more split reception from audiences, and only made around $2.3 million worldwide on an unknown budget.
Designated Hero: Dawn becomes this once she castrates Ryan in an act of Disproportionate Retribution and begins to take sadistic joy in biting off the penises of others. It's harder to sympathize with a protagonist when they become an open Sadist, regardless of their choice of targets.
Older Than They Think: Another example of a horror movie using a lesser remembered mythological idea and people not realizing it wasn't just made up for the film.
Diagnosed by the Audience: Teeth has something going on with him, though it's understandable with what he's gone through. For that matter, everyone on the island is a bit detached from reality.
