douchebag vs sewer rat

douchebag

noun
  • A jerk or asshole; a mean or rude person; someone seen as being arrogant, snobby or obnoxious. 

  • A sterile container which holds the fluid used for giving a vaginal douche. 

  • Any social misfit; a doofus, dork, or nerd. 

sewer rat

noun
  • A base and contemptible person. 

  • The brown rat (Rattus norvegicus). 

  • Used other than figuratively or idiomatically: Any rat that lives in sewers. 

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