To glance is to take a quick look at something or somebody. If a man glances at you, it is quite normal in most cases. He is taking a normal peek at you. Perhaps he is noticing your hair, your smile, or that bright red scarf you are wearing. Did you mean to use the word glance, or stare or glare? If he is engaged in a long stare, I would say he has a more curious interest in something about you, but you won't know until you speak to him I suppose. If he stares and smiles at you, I'd say there is some positive interest going on there. Not sure what you are actually asking..........