prostitute's client vs short-timer

prostitute's client

noun
  • the customer of a prostitute 

short-timer

noun
  • An employee who has given notice of their intent to leave. 

  • A soldier during the Vietnam War who had less than two months to serve. 

  • A person who would not be required to do a difficult or dangerous task. 

How often have the words prostitute's client and short-timer occurred in a corpus of books? (source: Google Ngram Viewer )