in the toilet vs vain

in the toilet

prep
  • Finished; at an ignoble end. 

vain

adj
  • Overly proud of oneself, especially concerning appearance; having a high opinion of one's own accomplishments with slight reason. 

  • Showy; ostentatious. 

  • Effecting no purpose; pointless, futile. 

  • Having no real substance, value, or importance; empty; void; worthless; unsatisfying. 

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