I have just rewatched the movie and there's a scene where Brian and Curt are on bed together. When Mandy entered the room only their clothes were on the floor but they were shown sleeping together before that. There's another scene after the Brian's fall in which Mandy comes in and confronts him and there's a black person sleeping on his bed. That's probably the black woman we see a few times in the movie. She's wearing the same Victorian wig as in a previous scene.