remorseless
adjective /rɪˈmɔːsləs/
  /rɪˈmɔːrsləs/
- (especially of an unpleasant situation) seeming to continue or become worse in a way that cannot be stopped synonym relentless- the remorseless increase in crime
 
- cruel and having or showing no regret for something wrong or bad you have done synonym merciless- a remorseless killer
- The sea was dark and remorseless.