Should I say something, he has a girlfriend?

Is it inappropriate for a guy in a relationship to grab another females lower back and waist constantly in a joking manner and he also will say he "loves" me? This guy we all hang out with does this to me and I really don't find the touching of the waist or lower back necessary and it is a rather intimate area. He has been in a long term relationship. It really bugs me and I want to say something and don't know how to tell him. He comes across as very nice, but I can't stand players and that is what I view him as because I feel he is way too overly flirtatious to be in a relationship. Before I say anything, am I overreacting?