backstory vs good guy

backstory

noun
  • The previous life and experiences of a person, especially a character in a dramatic work, but also a real-life person. 

  • A fictitious account of a person's history designed to conceal their actual history and motives. 

  • A prequel. 

good guy

noun
  • A hero, particularly a protagonist in a story. 

  • An all-around pleasant person; usually a man. 

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