The fourth of the eight steps is called Samma kammanta:
Right conduct or right behavior. It has been stated as:
"Do not destroy any living creature; take only what is given to you; do not commit any unlawful sexual act." 9
The prohibition against engaging in sexual misconduct is also listed as the third of the five Buddhist precepts. Sometimes it is expressed as simply forbidding adultery.
When applied to sexual behavior, this step would seem to imply that one must:
Practice safe sex to minimize the chance of passing an STD to a sexual partner that could, in the case of HIV and HPV, cause death.
Engage in only consensual sex. It is a bit of a stretch, but forced or manipulative sexual behavior could be interpreted as theft.
Avoid "unlawful" sexual acts. This is a difficult phrase to interpret.
From a legal standpoint, the U.S. Supreme court decided (Lawrence v. Texas, 2003
) that all private consensual sexual activity between adults is lawful. Unlawful sex in the U.S. would include activity between an adult and a child, sex in public, sex that is forced, sex for money, etc.