Who is Michael from Black, White, and Jewish: Autobiography of a Shifting Self and what is their importance?

Michael was Walker's boyfriend in San Fransisco. He was at least four years older than Rebecca and her longest serious relationship. When Walker is fourteen, she became pregnant with Michael's baby, a pregnancy ended by abortion. Soon after, Rebecca chose to attend a private school, a decision that divides the couple. Michael claimed that the school caused Walker to act too white. Their relationship ended when Rebecca fell in love with a technician working on her mother's film. Michael was irate when he learned that she chose a white man over him.