Me and my mate.

I have recently been involved in a serious relationship with a man of 75 years. I however am only 23. I guess our problems start with sex we both agree doggy style is our favorite postion but when i have him bent over punishing his throbbing hole he likes to reach back and grab my balls. This may sound like a good thing but he almost never clips his fingernails and I started to get cuts on my sack. When I showed him how much pain I was in he held me down and poured rubbing alcohol on it and called me a little bitch boy. But it doesn't stop with that, in the middle of the night I enjoy waking up and making love but this is the time his dentures are soaking. He always insist on kissing a lot without them but sticking my tounge in his mouth creeps me out because all I can feel is gums. I mean cant he just put the teeth in when we start to have sex? I dont know what I am going to do. I am afraid the only reason I am with him is for sex which is starting to become a living hell and the ben gay after shave smell is starting to make me feel sick... Im a young man with my life ahead of me what should I do?