lady of the evening vs moll

lady of the evening

noun
  • A female prostitute. 

moll

noun
  • A prostitute or woman with loose sexual morals. 

  • A girlfriend of a surfie; blends with pejorative sense. 

  • A female fan of extreme metal, grunge or hardcore punk, especially the girlfriend of a musician of those aforementioned genres. 

  • A girlfriend of a bikie. 

  • A female companion of a gangster, especially a former or current prostitute. 

  • Bitch, slut; an insulting epithet applied to a female. 

How often have the words lady of the evening and moll occurred in a corpus of books? (source: Google Ngram Viewer )