Touching the small of your back?

OK. one day I turned a 'journal' page into my teacher, and he just left it on the desk. then this guy, who hasn't ever seemed interested in me, went over and started reading it. I didn't think much of it, cause he probably just wanted an example, and it wasn't very personal. a couple days later he sits next to me in the library and asks to borrow a project handout that I was using, and he asked me for help. today, he brushed by me and put his hand on the small of my back.

mean anything significant?
Touching the small of your back?
Post Opinion