Johnny Deeper is a fictional young boy who appears in a number of sexually explicit anecdotes referred to as "Johnny Deeper Jokes". These stories are passed around elementary school age males, and may to many represent first exposure to sexually themed humor.
Most stories center around the character Johnny Deeper fornicating with teachers or being vulgar in the classroom; hence the series enduring popularity with the age group. Some jokes are very simple and play only off Johnny's surname, while others, far more complex, just represent Johnny as a vulgar, but ultimately innocent and loveable elementary school student.
Little Johnny Deeper's mother comes home and catches him on his girlfriend and yells, "Johnny Deeper" and Johnny replies "Gee Mom, I'm in as deep as I can go".