When walking how often does someone tail someone very closely and stay very closely behind the person as they walk at a brisk pace? I think someone might be hiding from me, because I saw someone do this when I was walking toward them, but did not see them until they were right besides me. It seemed to me that the person was using the person in front as a shield.

I didn't want to turn around and face my stalker but I didn't want them following me either, so I took a strange route to work, thinking I'd eventually turn down a road they didn't want to go.
Didn't work. Couldn't shake them off. Eventually I stopped and could see them right behind me. I plucked up the courage to turn and face them but as I turned, they ducked around behind my back again. I was very worried at the point.
It was only then that I noticed the black shape behind me was the black velcro tab hanging off my umbrella.
http://oi45.tinypic.com/m9vitv.jpg
black = me
red = person who is walking closely behind another
orange = some random person