Let's see, I'm kinda tall and a bit thin but it's nothing major; probably the main thing that distinguishes me and is the fact that I have thick-ish black eyebrows and a low brow (owing to a big forehead), and as such it means that whenever I'm doing something like writing or texting or even having a drink, I glance back up at someone and often get the following:
"Dude what's with that look!?!?"
So yeah, sadly it looks like I'm glaring at people half the time - it's completely unintentional.