In short, it is your high school D&D game..you know the one..that one.., if all of the table banter was part of the actual story line. If all of the references to other pop culture, all of the immature dick and pot jokes were actually part of the game. No doubt some aspects of the humour are more or less relevant depending on when you went to high school and who you hung out with. More or less homophobic, more or less pot references, more or way, waay fewer breasts.
But if you have any nostalgia for such times, or can laugh at yourself (or at least who you were) its well worth seeing.