Which perspective on how to decide matters of sexual morality is most convincing to you: Utilitarianism, Kantianism, or Natural Law?

Which perspective on how to decide matters of sexual morality is most convincing to you: Utilitarianism, Kantianism, or Natural Law? Why? If you believe that more than one of these three (or any other perspective) ought to be used to judge sexual behavior, which do you consider most important? Why?