There is a running joke among my friends about Italy's police being as incompetent in real life as they are portrayed to be in giallo flicks; the reportage about the "Monster of Florence" is a case in point: the police seemed so incompetent that no less than four suspects have been convicted of the crimes without conclusively or convincingly proving guilt--for which the police justly faced a good deal of scorn and ridicule. Apparently this dim view of law and order in Italy is nothing new; this early 19th century novel offhandedly remarks that Venice is a place were murders...just sort of happen...without the authorities that be getting interested in putting a stop to that sort of thing.
Okay, so the setting makes Venice seem like a squalid murderdump where life holds no value. Surely the protagonist will contrast such a sordid backdrop? The "hero" of this Gothic romance is essentially Blue Velvet's Frank Booth in Gothic drag. He overhears a plot to kill someone, but...doesn't really feel arsed to get involved. He does, however, learn of a plot between a rich woman and her side piece to run away together. Since it is the night of the Carnival, he decides to dress up as said side piece, worm his way into the rich lady's mansion, and have sex with her. (He's wearing a mask when he comes in and the lights are out when they clamber into bed, see, so she can't tell!) Afterward, he runs away with her (still in the mask) and eventually takes it off in another town to say "lol, I hit that!" Happy that he got into her skirts, he ditches her after dropping the mortifying knowledge that she just got tricked into having sex with a stranger.
When he comes back to his own familial mansion he blurts out something that he shouldn't in front of the help, so he pulls out a dagger, puts it to the throat of his servant, and makes him swear on the Virgin Mary that he won't repeat his unfortunate mouthsounds.
This guy is the protagonist. The novel is named after him.
This is all fifty pages in.