This has to stop

Me and my sister were at this indoor food market place with lots of different shops and small bars, we chose this particular food market because it had good food. So we walk up to the place we want to order chips and this guy who had been standing in the entrance to the very small shop had instantly begun gawking at my sister and staring her up and down. Bear in my mind my sister had a small stain on her white top because she dropped ice cream from earlier on whilst we were out. So this guy continues staring with no shame at all and at this point is in a very small vicinity to us. There are lots of people sitting on benches around us and it’s busy in the market. This guy’s friend realises what this guy is doing and just laughs, and continues to laugh whilst this other guy is blatantly staring at my sister looking particularly at her top and licking his lips. He stares as if he’s been deprived of food for 5 years and finally encounters some. This continues for another minute or so whilst we try to get in the shop to order, which btw he is blocking the entrance to. And then as we attempt to move past him he reaches out to touch my sisters arm saying excuse me miss whilst staring and smiling at her. Bear in mind my sister is under 20 and giving no response at all and i even gave the dirtiest look to the guy and said have you got a problem and he still continues to look. Eventually he realises he better leave before i start to raise my voice and embarrass him. I’ve experienced so many incidents like this where strange men feel entitled to own women’s bodies with their eyes and have no shame in not lowering their gaze