Who is William from Cannery Row and what is their importance?

William is the late watchman (bouncer) at The Bear Flag Restaurant, William is a dark, lonesome man who tries to befriend Mack and the boys but is rebuffed (inaccurately) as a pimp. When even bums reject him, William decides suicide is the only option. The Greek cook does not disagree—or believe he will go through with it—and William drives an ice pick into his own heart. Everyone likes his successor, Alfred.