Who is The Pussum from Women in Love and what is their importance?

The Pussum is one of the characters in the Halliday crowd, whom Birkin knows in London. She is a model and a hanger-on, with an affected lisp that makes her seem childish. She has an affair with Gerald Crich, who is drawn to her soft femininity, but she is really only using Gerald to revenge hrself on her lover Halliday, to make him jealous.