"Love is the Law, love under will."
Except as motivated by love and the need to express love, all acts are unlawful. Most unlawful of all, are those acts which seek to extort love by pretense: by denying one's own will or self to deceitfully appear to be food for another's appetites. Next come those acts which are based on will, but not on love. If both of these two types of unlawful acts were purged from humanity, we would live in utopia.
Harm none, and beyond that take the responsibility to choose your own actions based on wisdom regarding their consequences, is the only rule a non-fool really needs.
( * Thelema is the Greek word for will and is related to the Greek for love, Agape. The Greeks did not recognize romance as a form of love, they had an entirely different word for it, Eros. )