impure vs pervy

impure

adj
  • Unchaste; obscene (not according to or not abiding by some system of sexual morality) 

  • Containing undesired intermixtures 

  • Unhallowed; defiled by something unholy, either physically by an objectionable substance, or morally by guilt or sin 

pervy

adj
  • Behaving or looking like a sexual pervert. 

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