As others have said, this is P4P. You are buying her time, and a fantasy/performance she puts on for you. It works best if you believe the performance, like any play or movie, which can be confusing.
She may like you, or she may not. If she is good at this, which she is or you would not want to spend more time with her, you will never know for sure. Yes, you will believe that she likes you, but that is part of the fantasy. If you are a good customer, you might get some special treats. You always have the option of demanding special treats, and if you do that you might get them. Asking her to join you for an OTC drink or dinner is demanding a special treat, no matter how you think you mean it.
You are paying for every special treat. You probably will pay less if she spontaneously offers you a special treat, and more if you demand one and get it. Business tends to work that way.
There are going to be times when the fantasy becomes reality, you do become friends, and it stops being P4P. That is rare, but it happens. It also is quite different from spending extra time together before or after a paid date.
Listen to the experienced guys - pay for your time, respect the time, enjoy the time, and then head out. If she is open to something else, she will let you know.