Coin bj [nsfw]

It's not a coin. It's a token. You visit the front desk and there's someone there who speaks your language. They give you the token and you go down to where the whore is and giver he the token. That way, even if she doesn't speak your language she knows what to do.

This is the way it used to work in basically every Mediterannean port city, in like 400 AD.