exchange flesh vs show someone one's etchings

exchange flesh

show someone one's etchings

verb
  • A clichéd innuendo used to offer to bring someone to a private location in order to have sex, to show a place where people can engage in sexual intercourse (alternatively replacing "someone" with a phrase starting with to) 

How often have the words exchange flesh and show someone one's etchings occurred in a corpus of books? (source: Google Ngram Viewer )