Walter Mitty vs sentimentalist

Walter Mitty

noun
  • An imposter, especially one falsely claiming to have done military service. 

  • A sad or pathetic person given to flights of fancy; a daydreamer. 

sentimentalist

noun
  • A person who is sentimental. 

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