Ever heard of a graphics artist named Tom Poulton?
According to Wikipedia, ( https://en.wikipedia.org/wiki/Tom_Poulton ) Tom Poulton (1897–1963) was a British magazine and medical illustrator who provided artwork for a range of publications including the British Journal of Surgery and The Radio Times. After his death it was discovered that he had also secretly produced hundreds of sketches and finished drawings of men and women engaged in a wide range of uninhibited sexual activity.
Here's one of his works, dating back to a time when naturist resorts were called "Nudist Clubs". He's playfully highlighted the (largely fictitious) problem of the unwanted erection amongst the male club members, something which is often envisioned by those who have never actually been to a naturist venue. The poor guy is in total despair as he fails to keep it down, in spite of (or perhaps because of) the camera poised to take his photo along with his beautiful companions.