remorselessness vs sorrow

remorselessness

noun
  • the characteristic of lacking remorse 

sorrow

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

  • To feel or express grief. 

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

  • unhappiness, woe 

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