re·morse·less 
/rɪˈmoɚsləs/ adjective
/rɪˈmoɚsləs/ adjective 1 : very cruel and showing no pity or sympathy for other people : merciless
▪ a remorseless murderer 2 : continuing in a way that does not end or that seems impossible to stop
▪ his remorseless pursuit of justice
▪ a remorseless murderer
▪ his remorseless pursuit of justice
— re·morse·less·ly adverb
▪ She attacked her opponent's position remorselessly.
▪ She attacked her opponent's position remorselessly.
