"...and dance as if no one is watching."
Someone is watching.
Listen to the voices in your head... or at least the ones you agree with. In my opinion, the composition is great as it is. They're dancing in a public plaza. They don't care if anyone is watching, as they are enjoying themselves.
Thanks for sharing.
Nice photo. I would leave the passer by in the frame. He adds something. You see, I want to know more about the dancers. They are faceless to me. I wish you had a profile shot like this. That would satisfy my urge to know more about them. That is why the passer by adds to the photo. Without him it seems to me it would be too lifeless.
I think the "he passer-by" is a she but either way he/she doesn't fit in. Might be OK if there were several people passing by but an empty plaza adds to the atmosphere of the couple being completely wrapped up in each other and gives it a kind of eerie/ romantic flavour.
I agree with what Photo Engineer said too.
I like it as photographed, it has symmetry left open pane, middle pane of focus with the dancers and then our passer-by in the right. If you just have it with the dancers it becomes only about them. If you leave in our passer-by, well the scope is broadened.
I would leave (and I agree she's female) her in. The only way I would crop her is if she were walking OUT of the photo.That would imply her disinterest. Also the angle of her walk across the plaza implys she IS interested, but not intruding.