A figure of speech in the deep south referring to a person that is trying to hook up with the same person that you are trying to hook up with.
Bill: Hey Tom! I took Kate out on a date last night. We had a good time.
Tom: WTF Bill! Why are you runnin my trot lines!!! I have been trying to get with Kate all week man.
Tom: WTF Bill! Why are you runnin my trot lines!!! I have been trying to get with Kate all week man.