From Discworld & Terry Pratchett Wiki
A beggar and member of the Canting Crew, not formally a member of the Beggars' Guild. Altogether Andrews made his first appearance as a beggar who newly joined the already-infamous Foul Ole Ron and company (in The Truth'). Andrews has eight personalities and none of them answers to the name "Andrews"; the Duck Man, the intellectual among the Crew, is of the opinion that Andrews had been just an average psychic man with too many spirits possessing his body and overrunning his own personality. Andrews' facial expression changes as his body passes between the controls of the various personalities, and his speaking voice also changes. In times to make business decisions or to think up a scheme to protect a special dog, the personality "Lady Hermione" is the most capable.
His personalities are variously called: Jossi, Lady Hermione, Little Sidney, Mr Viddle, Curly, The Judge, Tinker and Burke.
Burke has apparently only emerged once, the results of his appearance were unpleasant enough to cause the other seven personalities to keep him buried.
This statement, and the vote carried out to see if the Crew should become Paper-of-News sellers, shows that all eight personalities are active all the time, instead of seven dormant and one awake. It must be like having eight children trying to drive one remote-controlled car on Christmas morning. Despite this, Andrews is generally seen as the sanest member of the Canting Crew as at least five of his personalities are capable of holding a coherent conversation with others.
He is not alone in his affliction: in Carpe Jugulum, Nanny Ogg refers to an otherwise unnamed bell ringer in Ohulan Cutash whose psyche is occupied by seven personalities, three female and four male (including his). His indwelling spirits have all paired off together, leaving him the gooseberry whose function is to do the boring but necessary things, like breathe and move around. Apparently all seven fight for control of his tastebuds whenever he has a drink...