Massage Spa Analysis

I get massages regularly 'cause I have a bad neck from years of weight lifting. A woman told me about a massage place that's below market. She assured me it was a legit place. Rates are about 50 - 60 % of the going rate. It's not crazy sketchy. But something about the place always made me think it was a happy ending spot. There's a neo sign and the entrance is in the back.

I've been going for years and got nothing but good massages until recently this chick gave me a happy ending which has happened several times now. Here's my question. There is a Jacuzzi in a back room that I see massage therapists (women) go into with men. What do folks think is happening back there. I asked my happy ending girl about who barely speaks English (everyone is Chinese) and she didn't seem to want to talk about it. I also asked her if all the girls give HJ and she said she doesn't know.