prostitute oneself vs whore out

prostitute oneself

verb
  • to perform sexual activity for money; to work as a prostitute 

whore out

verb
  • To prostitute, take advantage of, exploit, show off; to hire out or provide to others like a whore. 

  • To pimp; to offer (one's sex partner) to others. 

  • To do something debasing for money. 

How often have the words prostitute oneself and whore out occurred in a corpus of books? (source: Google Ngram Viewer )