answer: #Person2# says Leo and the young woman are dating each other, which surprises #Person1#. They think it must have been love at first sight.
documents: #Person1#: Hey, there's Leo. I wonder why he's walking arm in arm with that young woman. 
  #Person2#: It's as plain as the nose on your face. They're dating each other. 
  #Person1#: You're pulling my leg! She must be thirty years younger than Leo. Talk about robbing the cradle! 
  #Person2#: Well, you can bet this relationship's going to be a flash in the pan. 
  #Person1#: It must have been love at first sight because I know he didn't have a girlfriend last week. 
  #Person2#: I think you are absolutely right. Actually, my father proposed to my mother after knowing her only two weeks. They got married a month later.