If I search Google for "butt gif" I see these top 3 results: human butt getting slapped, Simpsons principal twerking, and someone's face in someone else's rear.

If I search Google for "butt gif" I see these top 3 results: human butt getting slapped, Simpsons principal twerking, and someone's face in someone else's rear. Of course our subjective definitions of sexual content may differ, but I wouldn't consider these to be any less sexual than the pony.