firebath vs massage parlor

firebath

noun
  • A bath in intense heat; sauna. 

massage parlor

noun
  • A place where clients can pay for a massage. 

  • A place that offers a happy ending (a hand job) after the massage; a front organization for a brothel. 

How often have the words firebath and massage parlor occurred in a corpus of books? (source: Google Ngram Viewer )