jo vs lovebug

jo

noun
  • Darling, sweetheart. 

  • The staff used in the Japanese martial art of jodo or jojutsu. 

lovebug

noun
  • A person who is in love; a sweetheart. 

  • An insect, the honeymoon fly (Plecia nearctica, family Biblionidae). 

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