Originally hired to inhume the Counterweight Killer who rumour had led him to believe was the Agatean visitor Two Conkers. He was prevented from killing him in Saturnalia’s casino by Lewton's deliberately getting in his way, knowing that assassins may not kill people not under contract.
After there is a break-in at the palace the Patrician puts out an open contract on whoever was responsible. Remora suspects that it was a werewolf, and that the private investigator Lewton was the culprit. Given that Lewton's grave is empty, this is a fairly strong bet.
A Remora is a small fish that lives its life as a parasite or a cosymbiont on the outer skin of a shark (genus selachii, incidentally) - its sucker mouth is lined with thousands of small sharp teeth which once attached never really let go.
A possibility is that Remora married into the Selachii family from a lower social status, and they are now obscurely regretting it? Although unless Nanny Ogg naming conventions apply here (and would somebody from a lower social class marrying a Selachii take the more powerful family's name?) this is a lot less likely than it once seemed.