Unqualified commitment
A college man walked into a photography studio with a framed picture of his girlfriend. He wanted the picture duplicated. This involved removing it from the frame. In doing this, the studio owner noticed the inscription on the back of the photograph:
“My dearest Tom, I love you with all my heart. I love you more and more each day. I will love you forever and ever. I am yours for all eternity.”
It was signed "Helen,” and it contained a P.S.: “If we ever break up, I want this picture back.”