The problem, the way I see it is how you titled the photo...
We have NO idea that was taken in St. Peter's square. Since the location is not the subject. The subject(s) are the couple in the photo. Their interaction between each other could happen anywhere. Now, I'm not a street photographer, but when I look at street photography I expect two things: 1) The photo to get me to ask more questions that it answers. 2) The subject(s) interaction should be characteristic of the location (if you chose to include the location in the title and location is not directly obvious.)