It's a bit of a lightweight introduction to a convoluted subject drawing in sociology, legal history, customs which may date back beyond Anglo-Saxon times, literature, morality, religion, diversity, disease. It seems too much to condense into only 166 pages without omitting important details. One is tempted to think that someone suggested, “Think of a title that has sex in it. That'll be a seller. We can always fill out the contents with illustrations, sonnets and Shakespeare.”
As far as it goes it's entertaining rather than educative. A suggestion of Monty Python “nudge-nudge, wink-wink, say no more” here and Blackadder series two “rumpy-pumpy” there. Salacious poesy taking the part of Donald McGill saucy seaside postcards or Carry On films at their most naughty but nice. I felt by the end that I had enjoyed the experience and yet found an explanation for my enjoyment obscure. If I may slightly misquote Rosalind from As You Like It, “My affection had an unknown bottom, like the bay of Portugal.”