I have been dating this guy for a few months and we get along great and can't keep our hands off of each other whenever we are together. We also engage in some dominant submissive sex play.  I've stayed with him 3 times so far and have given him at least 2 blowjobs each time, but he does not return the favor and doesn't even have sex with me. And yes, I've asked. He always compliments my body and enjoys looking at me. I am starting to get concerned...