I have. Started as a client, dated, went on hols, lived together. It wasn't without a lot of difficulties and ultimately we split up, but we are still friends and don't regret it.
I think sometimes clients see escorts as some exotic alien lifeform we are trying to communicate with and understand. But they are all someones daughter, sister, friend, mum sometimes , and can need love as much as the next person.
So, yes, respect the boundaries and don't express undying love unless you have a relationship separate to business, but if there are feelings there on both sides, there are ways of broaching it, no less awkward than with a girl you like in your office or whatever.
I'm sure some girls here have relationships but I'd say some think it might be impossible.
Well it's not impossible. If my experience is any measure of it, it won't be easy but if there is genuine love, it can be done.