Who is Mei-li from Women of the Silk and what is their importance?

Mei-li was one of Pei's closest friends. When Pei arrived at the girls' house, she was assigned the bed next to Mei-li's. When Pei awoke on her first morning Mei-li greeted her with a smile. Pei and Mei-li became fast friends. Mei-li was fun and genuine. Mei-li was so friendly that she was loved by everyone and seemed unaffected by others' moods.