Sometimes dogs with strange behavioral patterns will try to mate with their owner's leg or other inanimate object. This is true for both male and female. Have you ever had that experience? How did you deal with it?
My 4-year old Retriever will sometimes try to hump my leg when he is very excited or when I am wrestling with him or playing ball. He only does this to me; he has never attempted such behavior with my wife or anyone else. I wonder if it is because I play rough with him more so than anyone else. I usually put my knee into his chest when he tries to do this.
I haven't yet owned a male dog. None of my females (all spayed) ever displayed this behavior. However... Hubster and I had this gorgeous male Russian Blue cat named Shadow. Before he was neutered we had a friend staying with us for a while. One night we were all in the living room just hanging out, watching tv and talking. Shadow jumped up onto the back of the couch, walked over to where Dave was sitting, and mounted his head!!! It was a hysterical shocker, to say the least!