What does it mean when a guy does this?

Men are dirt bags. Especially young men, who grope of older women. If he really cared for you, at least this is what I would do, he would learn to cherish and enjoy your company for you are, not what your physically made of. Physicality in a relationship SHOULD be (I stress should as it often is not) a product of a genuine love for the companionship of a person. If you feel his intentions are deeper than his physical gesture, which can be very hard to determine, then give him a chance. Stress that you want to take the physical aspect slow, if not keep it nonexistent, until you can fully see where his true value lies. If he has genuine feelings for you, he'll understand, and wait.