"Vittoria Corombona has asked us all to her ball on Saturday"

Vittoria Corombona (or The White Devil) is the name of a play by John Webster (1580-1625); it belongs to the genre known as revenge tragedy.

The play's central character, Vittoria Corombona, is a young woman from a Venetian family who is tried for adultery and the murder of her husband.

A real event, the murder of Vittoria Accoramboni in Padua in 1585, was the inspiration for the plot.

We can, of course, only speculate as to whether Waugh wishes us to read any particular significance into his choice of name.