Who is Herman from Junky and what is their importance?

Herman first meets Bill when Bill is fencing some stolen property. Bill describes Herman as a small, very thin man with a mottled yellow complexion and skin eruptions. Herman's mouth is usually drawn down at the corners and he is often rude and abrasive. Upon their first meeting Herman takes an immediate and intensely hostile dislike to Bill. After several weeks' of acquaintance, however, the two men become associates and eventual friends. Herman and Bill form a temporary partnership to peddle marijuana but give it up after awhile because it is not monetarily profitable. Herman is a consummate mooch and always manages to live with someone else, rent-free—at one point living with Bill. At some point after Bill leaves New York City Herman is arrested on unspecified charges. At the conclusion of the novel Herman is still incarcerated.