Little Johnny was passing his parents' bedroom in the middle of the night, in search of a glass of water. Hearing a lot of moaning and thumping, he peeked in and caught his folks fucking. Before his dad could even react, Little Johnny exclaimed, "Oh, boy! Horsie ride! Daddy, can I ride on your back?"
Relieved that Johnny was not asking more uncomfortable questions, and seeing the opportunity not to break his stride, Daddy agreed. Johnny hopped on and Daddy started going to town. Pretty soon Mommy started moaning and gasping.
Johnny cried out, "Hang on tight, Daddy! This is the part where me and the milkman usually get bucked off!"