The top one

Constance ran the scissors along the 4 remaining knots. She waited a while at the now last button. "This one off would expose your pussy all day long." she said softly, "this one, your belly. This one your diaphragm. So to humiliate you I choose this one!" she laughed and cut off the top button.

At the same time my dress stood out at the top. I now had a great cleavage and with every forward movement my breasts would be visible to the person opposite or next to me

At that moment there was a knock on the door. Who could that be?