What are personality traits of Punky from The Man Who Loved Clowns?

Because Punky is mentally retarded, he doesn't understand when people are laughing at him, and he sometimes joins in, which drives Delrita crazy, and she has made it her personal mission to protect Punky from the many bullies in the outside world. Even though he is in his thirties, Punky still acts very much like a child. He wears a cowboy hat, sings into an imaginary microphone, rolls broken crayons on his table, throws chicken bones behind the television set, and loves watching advertisement commercials.