A lazy rapist rapes in a very lazy manner. They are quite often unprepared and unenthusiastic about the episode. More often than not the rapist wont even finish, they'll simply stop and leave. They will not go out of their way to conceal their crime.
Jane: "I heard you were attacked in the park last night while you were out walking your dog."
Emma: "Yeah I'm lucky that he was a typical male though."
Jane: "Yeah, I heard you fell victim to a lazy rapist."
Emma: "He was that lazy he didn't even finish, he practically stuck his knob in then bailed after I asked if that was it."