The Gangster is married to the sister of Dominican dictator Raphael Leonidas Trujillo. It is not explicitly explained why he married her, but we can make some educated guesses.

First, we are told that they both met in the sex trade. Trujillo's sister, who is referred to as La Fea (the ugly one), had been a prostitute and The Gangster was a pimp who had owned a number of hotels that prostitutes used to ply their trade. The Gangster is ever the opportunist. He probably felt like being the in-law of a powerful man like Trujillo would help forward his own ambitions. In this he was right. This connects him to the avenues of power and likely made him a wealthy man. At least it allowed him to appear wealthy, with his several houses, fancy suits, and expensive cars that allow him to woo Beli. La Fea, however, is a jealous woman and has her brother's thugs beat Beli to within an inch of her life when she discovers the affair.

The Gangster is married to Trujillo's sister. She is an older woman, and certainly not the young bombshell that Beli is.

Apparently the Gangster and Mrs. Gangster met while both were working in the sex trade business there in the Dominican Republic. As we know, the Gangster owns several love motels and makes a lot of money as a pimp.

We are never told why the two married, but we do know that the Gangster's career clearly benefited from being the brother-in-law of the country's leader—why wouldn't it? We also know how charming he can be, based on his interactions with Beli, so it is possible he used that same charm and persuasion on the future Mrs. Gangster. One can make the assumption that the marriage was one of convenience, at least for the Gangster.