Why does this boy do this?

There's this boy, Eric, who will shout "Hey, Alexis" when I pass him in the hallways. He started it in January. He would also tell me to "Shut up, Alexis" or "Stop it, Alexis" randomly during first period.

I didn't expect him to do it this year. We had no classes together, and I don't really know him. But he has said something to me at least once a day.

One of his friends said something, too. "Hey, Alexis. Eric says hi." I didn't even know Sawyer existed until he did that. It annoyed me because all I need is another senior I don't know yelling at me.

We had a field trip a few days later. When I got off the bus I knew Eric would be walking past. I don't know how, but I knew. He points at me and shouts "Hey, Alexis." He also started jumping up and down in the rain. A teacher in front of me turns around laughing. Later on I pass him and his friends again. Of course he yelled "Hey, Alexis." I turned around to watch them walk away when one friend yelled "Turn around." When I did I heard Sawyer say "I think she likes you." I have no idea what Eric said back.

We had a football game the other night. I went stupid decision on my part. Eric was there. He shouted "Hey, Alexis" like usual. I pretended like I couldn't hear him most of the times.

My friend's older brother used to play basketball with Eric and his friends. Sawyer walks up to her brother, and said "Is this your little sister? Eric makes fun of one of her friends. We always laugh about it." Her older brother told me that's just how Eric is, and he's just joking around.

Ever since last school year I've always wondered why he does it. I've always thought he was just being a jerk and making fun of me in some weird way, and I think what happened at the football game proves my theory. My cousin on the other hand just thinks it's his personality, and he isn't being mean. Also I don't know what to do when I go back to school and see him. I've considered slapping him, hiding from him, and ignoring him. Help me, please