I think first of all you need to make sure this guy knows that his actions were entirely inappropriate. It is not acceptable for him to touch you in this manner without asking for your permission, or having your implied permission. You have a choice to make, in that you either tell him that his antics were completely out of order and if he wants to touch you he has to get involved with you, or you can tell someone else, someone with more power, in which case this person may be looking at criminal proceedings.
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I drink too much, I smoke too much, I gamble too much. I am too much