and yes, just like a hospital resident who puts in 24 hour shifts, so too do Asian (et al) hookers who make more than any doctor in residency, put in some very long hours and rarely get a lot of time off when touring.
Most K-girls don't give off that cold/hard vibe, but it does happen and I can imagine it might give one the idea that she is not a willing participant, but I would chalk it up to either a lack of chemistry or a girl having a "bad day at work".
None of the better agencies will keep a girl around who gives off that kind of vibe, so it's unlikely that you are going to run into a lot of that kind of thing with the K-girls. but you are absolutely right, she is "stuck" in that apartment all day, just like a busy executive is "stuck" in his office all day.
One of the beauties of course about touring girls, on their off time a lot of them do like to "see the sights" and they quite often pick one of their lucky customers to be their tour guide.
I remember that is exactly how I started dating the last Thai hooker that later became a GF, I saw her on very short notice on a Sunday on one of her first days in Dallas, Sunday was not normally a work day, but she was new in town with nothing better to do, so she saw me on very short notice. After the session we were making small talk about what each one of us was going to for the rest of the day and I let it drop (sneaky guy that I am) that I might be headed to the local Thai market to buy some fresh seafood (not a lie, the best live seafood is at the Asian markets) she literally begged me to "Take me with you, PLEASE, PLEASE, PLEASE" and a beautiful friendship had begun. lol For the first year I knew her I would always book her through the agency, but she would tell me what time to book to be sure to be her last appointment of the day and we would stretch my one hour appointment into 6 or 8 hours going to dinner, drinks, movies etc. The next year she quit the agency and we no longer had to make any pretext of me being a paying customer.
The point of the story, is up until the time she met me, she had never been more than a block or so away from the incall apartment that she also called home, and she too was "stuck" in her apartment all day long and hadn't seen any of the city yet either, but it was NOT because she was a "sex slave"