Who is Butch Jan from Stone Butch Blues and what is their importance?

Butch Jan is another of Jess' butch friends in the Abba's crowd. Like Jess, Jan is a good-hearted woman, who has built up stone walls around that good heart. Jess looks up to Jan as an elder, but their relationship is complicated because of Jan's femme, Edna. Jess develops a powerful attraction to Edna after Edna and Jan break up.