There is this guy. We are not friends but we know each other. Always when I meet with him he stares very intensely at me without smiling. Once I was sending a message and when I looked up he was staring directly at me without smiling. He was in my right but I knew that he was staring at me because even his head was turned in my direction. That time I told him “ hi “ and he didn’t answer back he just kept staring at me without smiling and without moving at all. I stared back at him and it was really intense. It felt like we were the only persons in the room. Then I left since I saw that he didn’t answer me back. Another time he was talking with some of my friends and when I was behind this guy , but a little far away from him and when I said hi , he stopped talking and laughing and turned around and started to stare intensely at me without smiling. He was following my every move. When I got to them I told them hi and he stared for a time and after that he greeted me back and after that he still stared at me for a little time. And there were other people that he knew and when they greeted him he didn’t stop talking or laughing. He Sometimes greeted them back and that was all. why does he behave this way? Why does he stare at me without smiling?