Boyfriends dad

I need some advice. I always feel uncomfortable around my bfs parents because his dad always has to make sexual jokes about us and some time he made a comment about my boobs. I hate being around him. I’ve told my bf this and he says his dad has always been like this and he doesn’t know what to do. I told him I would leave him if something doesn’t change. I feel the way his dad acts is disrespectful and gross. And to make it worse i know that if any one made those same comments about his daughters, he would lose his mind. What should I do