From the Publisher's website:
kill puppies for satan is a roleplaying game. you pretend to be people who do just exactly what the title recommends. it's 32 pages of blasphemy, obscenity, profanity, not honoring thy father nor mother, and coveting thy neighbor's ass. or other pet.
in the game, when you kill a puppy (or other animal), you get points of evil. you spend your evil to do supernatural evil things, like start fires. there must be fifteen different ways to start fires with evil.
the system is minimal in the way that particularly irritates people who would rather be playing rolemaster or millenium's end. you have only six stats, for instance, and that's counting generously. one stat is how many people hate you. it takes about two minutes to make a character, longer if you need a calculator to add low single digit numbers.
the system isn't just small, it's also clever and flexible. in addition to the puppykillers, the main book includes rules for normal people, heroes, vigilantes, religious fanatics, space aliens (pretty much the pcs' only competition in the cattle mutilation department), sorcerers, ghouls, scientists, vampires, and demons, including a nice section on how to play lucifer himself as an npc.