Lou Epstein is one of three brothers who own the store where Alfred works as a grocery clerk. Although the brothers have given Alfred a job, they come to distrust him after the attempted burglary by Major and the gang. The Epsteins know that Alfred and James were friends, and James is the one perpetrator who is caught. Lou, however, takes a special interest in Alfred, partly because Lou was once a respected fighter himself, known as "Lightning Lou Epp." Lou ultimately believes in Alfred and offers him the opportunity to work the store's cash register.
Lou is another person who encourages life beyond the ring for Alfred. Lou and his brothers are also significant because they are Jewish shop-owners in predominantly black Harlem. As such, they are part of a difficult social dilemma and easy targets for racial slurs by Major in Chapter 1.