Who is Layzar the Butcher from Tevye the Dairyman and the Railroad Stories and what is their importance?

Layzar is an older man who is a widower. He is wealthy and wants to marry Tsaytl, Tevye's daughter. He is a coarse man and literally approaches getting Tsaytl as his wife as if he were buying a cow. His proposal is rejected by Tsaytl who wants to marry Motl the tailor.