I also forgot to add, it is violent (headshots cartoonily remove the actual head, and spray blood), but it's not seriously realistic. Terribly cartoony in most cases, especially running people over. The swearing is there, of course. Prostitution is more in the open then the previous games, although previous games certainly had missions based around it, being top down, you never saw much (and couldn't really tell genders even). Drug references are there too, although none are really seen in game (although the kill frenzies might be a reference to them, they're pill shaped) the drug SMACK is a core part of the gameplay (the Columbian Cartel, your supposed enemies, are drug smugglers).

Adult to the most part, but very cartoony ways of doing it to be honest. However, you can have a bloodbath, for sure.