Why does he do this........?

I asked before about this but I got one answer. 0.o

There's this guy I used to like, he goes to a different high school then me. But he and his school mates have to wait for their bus to their school in my school's lobby. (confusing I know) A few times he and his friends stand in front of the doorway (kind of blocking it)..only when I walk in. Once his friend opened the door while bowing too. I also see them looking at me a lot when I'm in the lobby talking to my friend.

Why does he (they) do this?

And should I be worried? It's kind of driving me crazy.