harass vs torment

harass

verb
  • To put excessive burdens upon (someone); to subject (someone) to anxieties. 

  • To persistently bother (someone, or a group of people) physically or psychologically when such behaviour is illegal and/or unwanted, especially over an extended period. 

  • To annoy (someone) frequently or systematically; to pester. 

  • To trouble (someone, or a group of people) through repeated military-style attacks. 

torment

verb
  • To cause severe suffering to (stronger than to vex but weaker than to torture.) 

noun
  • Any extreme pain, anguish or misery, either physical or mental. 

  • Torture, originally as inflicted by an instrument of torture. 

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