He must have a mean streak: it takes a certain remorselessness of soul to beat up, as he did, someone who's a partner on his programme. (conservativehome.blogs.com)
He did not just detail with forensic remorselessness the connivance of Gregory XIII in the St. Bartholomew's Day Massacre. (firstthings.com)
An encounter with his convict brother sheds a faint light on their shared remorselessness — the quality that supposedly makes The Iceman an intriguing character. (flicks.co.nz)