When the zombies came, most population centers in the world were overrun by the flesh eating ghouls in a matter of days. 95% of humanity was wiped off the face of the Earth. For most survivors, this was pretty traumatic.
But for Kevin and Iggy Sharp all this really meant was that they were stuck on their family's farm near Edgerton, Wyoming. Their grandfather had stocked the place since 9/11, so while people all over the state are starving, they are sitting pretty with a generator, video games, porn and plenty of ammo. Also, since they were essentially in the middle of nowhere it takes a long time for a dangerous amount of zombies to shamble all the way to the farm.
Kevin and Iggy spend most of their day playing Scrabble and occasionally shooting a zombie. One zombie they would never shoot is their best friend Jim. Jim is chained to a tree behind the house in the woods. Jim seems determined to kill and eat the brothers' brains, but this doesn't seem to bother Kevin and Iggy. They still think Jim is a great guy, at least for a zombie. They talk to Jim and seek him out for advice which is usually pretty much the same. ("Brains! Brains!")
With 95% of the population dead and nothing to do, Kevin and Iggy have to keep coming up with creative ways to entertain themselves.