Of course a monarch can never be a caitiff, cad, or bounder . . .much less a blackguard.
This miserable measure the wretched souls maintain of those who lived without infamy and without praise. Mingled are they with that caitiff choir of the angels, who were not rebels, nor were faithful to God, but were for themselves. The heavens chased them out in order to be not less beautiful, nor doth the depth of Hell receive them, because the damned would have some glory from them.Inferno by Dante Alighieri
That ain't good . . .to be a caitiff. The word comes from the Anglo-French of the 11th Century, following the name change William The Bastard of Normandy affected with his conquest of Harold the Saxon in 1066. It's better to be a conqueror than a bastard. Being a bastard is tough, because one inherits only his skin and is required to acquire a name for oneself. The word caitiff differs a bit from a bastard.A caitfiff is bastardized form of the Latin captivus or captive.
One was expected to die in combat, rather than become a captive. A caitiff therefore is someone who was there at a battle, and surrendered - called it quits.
From that military meaning evolved a judgment of character - one who surrendered was implied to be a wretch, a craven, a coward. Someone without the honor to die rather than surrender, because he lacked inner feelings of virtue and nobility. Such a craven person would huddle with other like minded self-interested cowards in a township.
A Cadet ( Capitellum or 'little head') was a townie. Someone who curried favor of his betters - not to the Manor Born. If you lived in a Manor, you were noble by birth and blood. From Cadet evolved the caddie, a low-born person who did the bidding of his betters. A Cad was one who strayed into a better circle of society by dint of service and might flirt and play the dandy with the Lady of the Manor, but a Cad who went over the boundaries was a bounder -first employed in our living language around 1550. The extent of a Cad's excesses would be semiotic -signals and promises of exhausting pleasures - and go no further.
A Bounder is a complete rotter, scoundrel, or near-do well. One capable of any and all manner of miscreance - a breaker of faith. One might trust Clive Ajouter-Sur -Un-Matelas, the family wine steward, to distinguish a claret from a Rhenish, but should not be altogether floored to find Imported Frog-eater bouncing on the Baldacchino Supreme atop of Lady Salope.
Clive has gone from cad to bounder. A Cad might intend to diddle Lady Cuisses-Chaud Salope, but a bounder will enact the deed.
A Caitiff merely will know what is going on in the chambre à oucher master
between Lady Salope and Clive and smirk and ooze about his daily tasks.
A Bounder becomes a Blackguard when he mocks, curses, thrashes and ultimately beats Lady S following a particularly Herculean assignation, confronts Lord S with the unhappy fact that his Lordship has been goated. . . has been goated vigorously and often, with a grand sweep of the cape given him by her Ladyship exits Salope Manor with a great Spanish leather Gladstone choked with Pounds Sterling and minor coin as well as trinkets and stones snatched from Lady S's horde of jewels and successfully publishes his 3rd person omniscient account of the decade long carnal romps with Lady S all the while plotting against Baron Vaine Salope's appointment to the Ministry of Exchequer.
A Blackguard is the top of the wicked tree here. Caitiff and Cads edge close to the boundaries of a higher social circle, while taking only those liberties afforded their place in life. Thus a Caitiff who ventures to flirt with Lady S becomes a Cad and Cad graduates to Bounder when seals the carnal deal. However, a Blackguard goes the extra mile in letting the world know about it - kiss and tell, don't you know.
I like bounders.