Who is Leroy Fleck from Talking God and what is their importance?

Leroy Fleck is a small-time criminal pretending to be an undercover cop, Leroy Fleck is the primary villain and a study in contrasts. He considers himself a tolerant man, yet uses the n-word in referring to African American acquaintances. He loves his elderly mother, yet pays her nursing home bills by murdering a man. He is an efficient, silent killer, yet ineptly tries to follow people in a distinctive, rusty, dented Chevy.