joy killer vs sorrow

joy killer

noun
  • killjoy (Someone or something that hinders fun.) 

sorrow

noun
  • unhappiness, woe 

  • (usually in plural) An instance or cause of unhappiness. 

verb
  • To feel grief over; to mourn, regret. 

  • To feel or express grief. 

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