intrigue vs troilism

intrigue

noun
  • Clandestine intercourse between persons; illicit intimacy; a liaison or affair. 

  • A complicated or clandestine plot or scheme intended to effect some purpose by secret artifice; conspiracy; stratagem. 

  • The plot of a play, poem or romance; the series of complications in which a writer involves their imaginary characters. 

verb
  • To have clandestine or illicit intercourse. 

  • To conceive or carry out a secret plan intended to harm; to form a plot or scheme. 

  • To fill with artifice and duplicity; to complicate. 

  • To arouse the interest of; to fascinate. 

troilism

noun
  • The practice of three people having sex, i.e. having threesomes. 

  • The practice of two people having sex while a third person watches (and may or may not take part). 

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