That genre being porn.
I'm not going to discuss that aspect of the book, as it doesn't interest me-I'm mostly doing this review as a favor to one of my readers (the author).
Carnageland, as its name suggests, is a very violent book. It's about a (very) short, (very) bloody invasion of a fairy-tale land by an alien empire, who sends in a grand total of one grunt to eliminate the inhabitants.
The appeal for me personally comes from the allusions and inventive plot tools.
Among the humorous allusions made are to numerous fairy tales and "fairy tale" stories, and to newer series with fairy tale roots, such as Harry Potter. A particularly sublime moment comes when the students of the magic school unleash a deadly weapon they developed on the invader: The Ninjerbread Man. (The other allusion that really jumps at me offhand were the Se7en Dwarves, which amuses me because I recognize that as a reference to
One of the inventive aspects of the book is the weapon carried by the invader, the "Doomshooter." It is basically a literal shoots-anything-imaginable gun. That is to say, you imagine something, the Doomshooter can shoot that object as a projectile.
So he fires a lot of fairly standard and obvious things, like freeze blasts, grenades, and death rays. But he also shoots things like universal death plagues, a vaccination for said plague (long story), an umbrella (in order to fly on wind currents), shuriken, a tentacle (!), and a giant iron spike to slay a very bizarre dragon (whose description sounded not at all like any traditional dragon I've ever heard of).
So basically, there are two major aspects to this story: (Rather extreme) sex and violence, and really clever, often cartoony ideas connected to fairy tales (and, to a lesser extent, alien invasions).
If that sounds like an ideal combination to you, this is probably your book. If it doesn't, well... It must not be your book.