I lived next to a Thoroughbred stud farm and in summer evenings used to go into the surrounding fields to meet mares and fillys. They were very willing indeed especially one or two who would greet me with raised tail and a lot of winking. They were quite tall though so hard to reach without a step ladder so most of the time it was just fingers and fist, but one time I balanced on the crossbar as she backed on to me. No question she was into it.