Mills-and-Boon vs gritty

Mills-and-Boon

gritty

adj
  • Containing sand or grit; consisting of grit; caused by grit; full of hard particles. 

  • Spirited; resolute; unyielding. 

  • Intense and starkly realistic; depicting harsh reality, especially violence. 

How often have the words Mills-and-Boon and gritty occurred in a corpus of books? (source: Google Ngram Viewer )