I think you'll find that medieval taverns and bath houses had more or less the same "service" as modern japanese hostess bars.
Pretty girls to serve you ( and make you spend more...) , but no prostitution as such. That was done by other Ladies of Negotiable Affection. Who often were "serving girls" as well, but didn't ply their actual trade Inside.
The "Hostesses" themselves were pretty much untouchable. They were the billboard of the tavern, and you did very much not "ruin" them, unless you wanted some Unofficial Justice visited upon you by either the bouncers, local peeps, or even travellers.
Quite a few of them had a sort of Idol status, and had songs and rhymes dedicated to them even.
That system itself tracks back to Roman travelling Tavernas, so has a looooong history.
The japanese Hostess thing is neither unique nor new...
