brothel vs sexual marketplace

brothel

noun
  • A house of prostitution. 

sexual marketplace

noun
  • Prostitution. 

  • The way in which people's desirability as sexual or romantic partners is evaluated. 

  • A location or situation in which people are looking for sexual or romantic partners. 

How often have the words brothel and sexual marketplace occurred in a corpus of books? (source: Google Ngram Viewer )