That's my defense too. I've been told that I'm kind of scary. Supposedly I look like I will punch you in the face if you try talking to me.  I never really realized this until one day when I was waiting for the metro and a guy approached me to ask me a question about my bike and the first thing he said to me was "please don't hit me, but..."    Then I asked my gf if I looked like I want to punch people when I am in public. She said, "yeah, basically."    So I guess I'm that guy. Fuck.