fornication vs sex life

fornication

noun
  • Sexual intercourse in general; sex. 

  • Sexual intercourse by people who are not married to each other, or which is considered illicit in another way. 

sex life

noun
  • That part of a person's life that is directly concerned with sexual activity. 

How often have the words fornication and sex life occurred in a corpus of books? (source: Google Ngram Viewer )