Who is Cassie from Women and what is their importance?

Cassie is described as a young, beautful woman with long, blonde hair. She meets Henry at a reading and takes him home. They meet again a few days later. Cassie works in the music industry, and she also knows Dee Dee Bronson, who she tells Henry has had a tumultuous life over the past few months. A few weeks later, Henry calls Cassie's apartment and a man answers the telephone and Henry does not call her again.