Gil Grissom from CSI.
Tom Bombadil is totally a dick. The ultimate battle between good and evil is raging all around him. He is apparently pretty much invulnerable to the power of evil, probably has huge powers of his own, and he can’t be arsed to do a damn thing about it.
I started thinking of laid-back characters, because to me being a dick is being petty and uptight. Naturally the first character I thought of was The Dude. But then I considered, and he did steal the Big Lebowski’s rug (which probably got P.S. Hoffman in trouble), which is definitely a dick move.
So I nominate Peter Seller’s character in The Party