pitiless vs unneighbourly

pitiless

adj
  • having no kindly feelings; unkind 

  • having, or showing, no pity; merciless, ruthless 

unneighbourly

adj
  • Not neighbourly; antisocial. 

adv
  • In a way that is not neighbourly. 

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