Christine is a chorus singer at the Ankh-Morpork Opera House, in Maskerade. She is a pretty, thin blonde with a tendency to wear white and use exclamation points at the end of every sentence!!!!! She is a beneficiary of the sad fact that star quality is a far rarer commodity than talent since she is actually an extraordinarily untalented singer, but the management favors her for her beautiful appearance and the fact her father has donated a good deal of money. She becomes the lead soprano of the company on this basis and the opera director has her lip-synch on-stage to the voice of Agnes/Perdita Nitt, a girl from Lancre, who is the 'wrong size' but can really sing. Christine's father told her that a "dear little pixie" would help her career, and she thinks Agnes might be that pixie. This may be comparable to Christine Daaé's belief in the Roundworld Phantom of the Opera that the Phantom is the "Angel of Music". This is also amusing because Agnes is always described as rather a large girl, eminently sensible, and not at all suited to the role of a pixie. Christine is friendly and kind but not particularly bright and can be unintentionally slighting. The "Phantom" in Maskerade accidentally tutors Agnes instead of Christine when Christine runs away from the ghostly voice coming from her mirror. Agnes realises what is happening and, in order to continue her training for a second night, she slips some herbs in to Christine's hot milk to make her sleepy. he rarely pays attention to anyone but herself as the following exchange indicates.
Christine - "What about your parents?"
Agnes Nitt - "Well, (realising that Christine isn't really listening) my father is the emperor of Klatch and my mother is a small tray of raspberry puddings."
Christine - "That's very interesting!! What do you think of my new dress?!"
The portrayal of Christine and Agnes plays with the ongoing debates in operatic circles between on one hand the traditional large women who can sing but don't look anything like the character they are playing - the 50 year old "fat lady" playing the part of the consumptive young heroine - and on the other hand the young thin woman who looks the part but doesn't have the lungs to sing the role. Agnes Nitt, fits the role of the large buxom traditional looking opera star while Christine who is a parody of Christine Daaé from The Phantom of the Opera fits the more modern opera soprano style.
Christine is to sing the lead in La Triviata a pun on La Traviata by Verdi. In the original Phantom, Christine is to sing the lead in Faust, which is the title of one of Pratchett's earlier works.