What should I do about him?

Well...there is this guy who I don't even know, yet every single day when he passes by my friend's locker(I always meet my friend by her locker once a day), he is always staring and smiling shyly at me. He even purposly walks as close as he can near me-and when I'm not there, he just sticks close to the wall, not the lockers. I'm the reason why he walks close and smiles. This has been going on for months and idk what to do about it. I found out who he was, and apparently, he's kind of strange, and very shy. What should I do? Does this seem at all creepy? Or is he just a secret admirer?