Why did this guy literally stop & stare?

I met this new guy at university today. He was sitting with a bunch of the other guys and at least twice when eyes met he froze - first when draping his coat over the chair & then later when getting up - then continued. The first time he did nothing, the second time he meandered over (to check a book) but said nothing while I was talking with the librarian.
Why did this guy literally stop & stare?
Post Opinion