It sounds to me like this guy is grooming you to be his personal money making machine.
You are under no obligation to him whatsoever, if I were you I would stay well clear.
Have a long hard look at yourself and where you want to go, and if you decide you still
want to be an escort, join an agency for a while until you learn the ropes.
I don't think you'll have much luck with the pictures to be honest, because even if you
insist on having them back, the chances are he'll have made copies. If you join an agency
they'll get a reputable photographer to do some shots for you. At the end of the day, you've
no way of knowing what he's going to do with them, but it's your word against his that money
changed hands, and you're not a "known" escort if you see what I mean. In reality they're
probably just for his personal pleasure.
Don't worry about finding sex with a vile guy a turn-on, I've had some shocks in my time, lol.
Anyway, post and let us know how you get on. xx