Different places have different laws about when you are legal to drink. In this specific example from The Fake Redhead, we don’t know where these people are or what the rules about about drinking in that place, but we do know that there are rules.
It is also clear that they have some sort of ID that fits into a wallet. Having discussed crypto currency at length with someone close to me, I do know that not all wallets are physical and I think we all know that not all IDs are physical either.
Most likely this prompt is for a modern time frame, but nothing says you have to use it that way. If you wanted to put this far into the future for a science fiction story, you could. Your character could be trying to get into an alien bar on a far off planet. Or maybe it’s a high fantasy setting in the far past and it’s a potion bar. Maybe it’s not alcohol they are after drinking, but a hallucinogen or something that makes you stronger for a short while.
There are all sorts of possibilities you can turn this prompt into. The very fact that it can be used for a modern setting allows for a lot more wiggle room of genre.
Another interesting thing here is the relationship between these two people. I don’t think they have a close one or the first person would not be asking if the second was legal to drink, unless the qualification for being legal was something other than age in which case that changes everything. They would know how old the person was, or at least know if they were over or under the age of legal drinking. On the other hand they clearly don’t care a lot about legalities if all they care about is if the ID says this person is legal and that is definitely the implication here.
A fun way to potentially use this prompt is kids playing pretend. They could be repeating the general idea of conversations they have heard, while getting the details wrong or if they are older, they could be making up their own rules. This could be the entrance to a pretend tea party.
As with so many of these prompts, this is a lot of ways you could play this and the characters, no matter what genre they are in sound interesting. What genre do you see this story falling into? Would you stick with contemporary as the most logical or slip into a different genre that changes the meaning to this conversation in some way?