It's hard to describe. Well, it's not hard to describe the plot, but it would sound really goofy, which it is, but it's amazing. This dude has a cat who can turn into lock picks or a grappling hook and he has to defeat a tentacle monster. And it's full of puns. But it's not really about that. You see what happens when I try to describe it? That's like saying Scott Pilgrim was about a slacker who punches people.
So you should just take my word for it and read it.