GirlHouse is a fairly effective slasher horror flick. It doesn't break a ton of new ground or anything, but it's tense, has a solid setup, and some really brutal violence. The characters were decently sketched out, if not hugely developed, but don't think the film was too concerned with that.
The entire house where much of the film takes place is the perfect setting for a slasher horror film, and the director makes good use of it through a variety of intense scenes. The film does have a decent amount of nudity, but considering the subject matter, it's not excessive. It's been a while since I've seen a solid indie horror slasher flick like this one, and I would say overall it delivers in a number of ways. If you're into that type of horror, I would recommend checking this one out.