"You know, you're rather short."

To emphasize his point, he walked over and stood in front of you, pushing your face against his chest.

As someone at a normal or average height, of course this lanky bitch is going to be a lot taller. And Satoru being the tease he is, likes to pick on you for it.

Of course he doesn't mean anything by it, and if it bugged you, he'd stop.