heartless
adjective /ˈhɑːtləs/
  /ˈhɑːrtləs/
- feeling no sympathy for other people synonym cruel- The decision does seem a little heartless.
- What a heartless thing to say!
- Police were quick to condemn this heartless theft.
- How can you be so heartless!
 Oxford Collocations DictionaryHeartless is used with these nouns:- monster