|Occupation||Banker, Mental patient|
|Physical appearance||stout, goatee beard, has only nine fingers|
|Parents||Joshua Lavish (father)|
|Relatives||Pucci Lavish (sister) and many others|
A member of the long-established and honourable (they've got old money, which gives anything an honorific) Lavish family: one of those long-entrenched upper crust families who, in theory at least, can contend to gain the Patricianship for one of their members. The nearest thing they have to a plausible candidate, at the moment, is Cosmo.
Educated at the Assassins' Guild (although he did not take the Black Syllabus), Cosmo, like other members of his family (such as his sister, Pucrezia "Pucci" Lavish), holds a minor directorship at the Royal Bank of Ankh-Morpork, and is not an ally of Moist von Lipwig. Moist, upon hearing that Cosmo did not graduate as an active Assassin, wonders out loud if Cosmo had taken a note in from his mother to the Master to excuse him from "stabbing practice".
Cosmo favours black-coloured clothing, although as has been mentioned elsewhere, this is only really stylish on people who are not carrying excess fat. Similarly, a goatee beard only looks stylishly sinister on people with only one chin: Moist thought of Cosmo's as being seriously misplaced and pitied the barber.
Oh, and he is also obsessed with Vetinari, neither a wise nor a sane thing on the part of one who, it is suspected, entertains an ambition for the Patricianship.
Is trying to train his eyebrow to raise quizzically, à-la-Vetinari, as in his opinion this is the source of the fascination the man extends over people, and to which people bow down - or quiver in fear, either of which responses would titillate our Cosmo. Unfortunately, it seems as though the eyebrow trick is beyond him, and it appears to be a manic tic. If he could only get it right, then surely the Patricianship would be his without doubt.
His fascination with Vetinari extends to other sinister ways. He has his manservant/secretary Heretofore, (whom he calls "Drumknott" as, in the mistaken fantasy world inside his head, his servant really was Rufus Drumknott,) collect all manner of objects that have been the Patrician's - boots, a skullcap, his sword-stick... Of all of these, only the skullcap was actually Vetinari's, but that didn't stop Heretofore's scheming and money-grabbing from his master. Cosmo would also use his own personal killer, the assassin Cranberry, to clean up any 'loose ends' from these schemes. Despite having just about everyone involved killed, Cosmo predictably did not manage to prevent his schemes from coming to the omniscient attention of the Patrician.
The final knell of doom for Cosmo, however, was in his desire to own a similar signet ring to Vetinari. Made of Stygium it had to be kept in the dark, and, as it was too small for Cosmo, it affected his finger. Badly. He wouldn't take it off, and the gangrenous, suppurating horrors that it caused finally sent Cosmo over the edge into madness.
He is now detained for the foreseeable future in the Havelock Vetinari Ward of the Lady Sybil Free Hospital. Oddly enough he is content to remain here, surrounded by poor madmen who believe that they are Lord Vetinari. Cosmo believes that he is safe here, as no one would suspect that he is the real Vetinari, and while he recovers he has joined and bested his fellow patients in the eyebrow raising contest.
The name Cosmo is a reference to Cosimo de' Medici, a wealthy Florentine banker of the 15th century. In a Discworld context, this also fits quite nicely : the name Vetinari was originally a play on the name "Medici," and what could be more appropriate (as well as evoking the power-struggles of fifteenth century Italy) than returning to this original pun, as a "Medici" attempts to oust a Vetinari?
It is also a clear reference to the Borgias, of whom Cesare and his sister Lucrezia were the most notorious...
Pucrezia's nickname "Pucci" is a nod to the contemporary Florentine fashion designer, favored by the rich and stylish. Interestingly, Emilio Pucci's ancestors were another wealthy and powerful merchant family during the Renaissance who were firm political allies of the Medici.
And of course the greatest living proponent of the Eyebrow Trick was British actor Roger Moore, who made the character of James Bond all his own by strategic use of a single lifted brow to convey a variety of emotional ideas, such as surprise, determination, sophistication and sheer coolth, as befits one trained as an Assassin. Many have tied to imitate, but just made themselves look ridiculous rather than suave lady-killers.