Who is Cate from Sarah Kane: Complete Plays and what is their importance?

In "Blasted", Cate is a childlike young woman who goes to a hotel in Leeds with Ian. She is wary of Ian, who had an affair with her when she was a teenager before cutting off communication with her. Cate is given to fits of panic where she passes out and wakes up laughing. In the hotel room, Cate is insistent that she will not have sex with Ian, saying she is mad at him and she has a new boyfriend. She becomes distressed whenever Ian gets angry, brandishes his gun, or has a coughing fit. Ian makes repeated passes at Cate, which she rebuts, and he eventually rapes her, injuring her genitals. The next morning, Cate is obviously angry at Ian. She destroys his jacket and thinks of shooting him with his own gun. She performs fellatio on him and nearly bites off his penis. She is in the bathroom when the soldier enters the room, and she then escapes.