Hentai (means pervert)

My Tenjin Matsuri experience was perfect except for one thing. I was touched by a "chikan," the infamous Japanese term for those who touch other people's body parts without permission. I had thought my camera bag was pushing against my crouch as the crowd pushed on and I was being squeezed. Then I looked and it was the fist of the man next to me, and immediately put my camera bag in that spot.

I had no idea how long it had been going on. I also thought it was an accident until I thought about it more. Other Japanese I had been around had tried to keep distance from each other, and not touch each other in any way. While I was not paying attention (I was focusing on taking pictures), this man came and pushed me more and more to the side to the point where he was between me and the other guy who had been standing next to me the whole time before. At one point, I saw that there was a good amount of space between that chikan and the man originally standing next to me. But why was it that the chikan kept on pushing toward my side? He was so close that our arms stuck together a couple of times- the sweat glued our arms together. I tried to get away and finally was only able to do so by standing slightly behind him, but then that was when the fist on my crouch thing happened. It did not help that crowd behind me was pushing me forward.

Since I was on the wrong bridge and could not see the boats well, and could only hear but not see the fireworks, I left after I thought out the chikan thing. I figured out that he was a chikan and I left. I did not know what the appropriate Japanese reaction was. Could I yell at him? What should I say then? I have never been good with reacting cleverly to situations.