"It's so long since I've had sex I've forgotten who ties up who"

In this quote, Joan Rivers is making an amusing remark about her lack of sex. She is saying that it has actually been such a long period of time given that she has made love that she has actually forgotten the roles and dynamics of the act. The phrase "bind" refers to the act of bondage or being restrained throughout sex. By stating "who ties up who," Rivers is indicating that she has forgotten who takes on the dominant role in the sexual encounter. This quote showcases Rivers' sharp wit and ability to downplay taboo topics.