anus vs ying-yang

anus

noun
  • An impolite, unpopular, or unintelligent person. 

  • The lower orifice of the alimentary canal, through which feces and flatus are ejected. 

ying-yang

noun
  • Anus; asshole 

  • Penis 

How often have the words anus and ying-yang occurred in a corpus of books? (source: Google Ngram Viewer )