Empire of Sin will live up to its name apparently as Romero Games didn't hold back with their depiction of the gangster-infested prohibition era. Besides alcohol, gangsters will be able to contract STDs that could potentially alter in-game variables.
Gangsters marked the first part of 20th century in Chicago as they smuggled alcohol, besides other illegal activities. Most notably, Al Capone was the king of the crime in the area as he evaded the law while becoming somewhat of a celebrity and a feared person overall. Being a mere mortal, however, Capone couldn't evade two things - tax and death. Tax evasion led to his incarceration while syphilis led to Capone's death.
Well, it appears that some similar things may happen to the players' gangsters in Empire of Sin as well. According to PCGamesN , it's alcohol that will keep the gangster machine's gears running but that is not the only sin said gangsters will indulge in.
Brenda Romero, Romero Games co-founder, stated that she is not proud of it but "there were brothels and there were consequences" during the Prohibition era. Meanwhile, as players grow their gang they will come in contact with various characters, some of whom may not be monogamous.
They can come with that trait or acquire it as the game progresses, be it through combat or through their normal lives. Contracting an STD can have serious implications apparently as those gang members will continue to spread them to anyone they have a sexual relationship with.
Furthermore, traits can have an effect on gangsters' combat effectiveness as well as contribute to relations between gang members, positive or otherwise. Should those relations turn into negative, other gangs will apparently be able to exploit the weakness in their own bid for Chicago.