I don't understand the killer's motive. The killer stalks the girl throughout the runtime, with exception to that cliché intro kill. He stalks her, then at the end, abducts her, then he just kills her. He stalks her for DAYS! He lives in her house without her knowledge! He pees in her sink just to mess with her. Then, he just kills her at the end. I don't understand why he didn't just kill her from the start if that was his goal. He had a S&M dungeon all set up. It makes no sense!