You know those random events that you can choose to either keep watching (or going in some cases) about specific fetishes and whatnot? Those are the "tag enablers" so to speak.
So if you want the musk flag enabled for example, you gotta go through the event which you're given a prompt to sniff someone or someone's stuff (the gym towel event for those wondering). If you choose to sniff it, it's enabled and will stay that way until you disable them by repeating the event and choosing the 3rd option that appears (it's always something that hints at forgetting it ever happenend or something to that effect).
Normally, there's one trigger per region and they only appear at certain times of the day so just keep exploring until you bump into one.