Worried But Considering

I dont want to say how old I am exactly, but I have a boyfriend named roy and we met a few years ago now. he often calls me and I dream of sex with him but feel that if I told him that it would change everything in our relationship and given his age and my age it might not work out. I need some advice. He calls me and he does a lot of casual sex hook ups. I want to but not sure right now.