Sorry, what's 'normal' in your country ins not 'normal' in Germany. Here prostitution is 100% legal and 'institutionilzed'. There is no need to sneak around. Also it is not safe, for both the man and the girl, to go off-premises.
By English linguistic definition a 'brothel' is a place where sex with prostitutes happens on-site. In German: Bordell, Puff. Your description would fit so-called pick-up bars, which we do not have in Germany as institutions. Of course street hookers might hang out in some pubs waiting fro tricks, and some nightclubs/bars have separees and backrooms for on-site sex.
Thailand is notorious for the bar scene serving sex tourists.
However in Germany there are so-called 'Begleitagenturen', i e = escort services, which will procure a call-girl hooker for you at a high price.
There are also some very small FKK-Hotels which might fit your idea. But the sex will be on-premises.
You can also try to pick up a streewalker, if you can find one. But this is not safe and illegal in many cities (try the 'Strassenstrich' in Bonn).
Check the directories in fkkguide.cyberfreehost.com