A privileged young man and son of one of Ankh-Morpork's most socially prominent families. He was educated at the Assassins' Guild school, although it is not known whether he is a practicing licenced Assassin.
He was arrested by Samuel Vimes and brought before the Patrician for "not knowing his right from his wrong. Or his left." The arrestable offence was apparently one of having inflicted GBH on his manservant for negligently setting out his boots the wrong way round, so that young Selachii got them on the wrong feet. This so enraged Robert that he took a whip to the hapless valet, something which would have gone unremarked in previous years as "a fella's right to beat his own servant for being bone idle, what". But these are newer times: Vimes seized the opportunity to make an arrest, no doubt to reinforce the new rule of law to slow learners, the one that says nobody is above the law and nobody is privileged. A point of view reinforced by Vetinari (a man who himself was twice formally arrested by Vimes.)