bad apple vs unsociable

bad apple

noun
  • A person who is not wholesome, honest, or trustworthy, especially one who has an adverse influence on others. 

unsociable

noun
  • A person who is not sociable. 

adj
  • not congenial or compatible 

  • not desiring the company of others 

  • unfriendly 

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