The moment he touched you, he was guilty of assault - no excuse for that.<...>
...instead of getting the message and leaving me the hell alone, I finish whipping just in time for his hands to dart under the stall, grab me by the ankles and start dragging me under the partition into his stall!!!
But I have to ask, the part of your post in bold font above... does that mean you were masturbating? If so, right or wrong, it may have encouraged him. Again, I'm not saying that it gave him any right to attack you, but he may have interpreted masturbation in a public restroom to be an invitation.