The "Sexuality Standard" is a set rules underlying sexuality throughout the universe. These rules can be overruled depending on the biological nature of a species' sexuality or legallity of law regarding sexuality in a given society.
1. One shall not have sex with what is not a person.
This justifies homosexuality, robosexuality, sexuality with intelligent extraterretrials and so on. It forbids bestially or sex with what is not a person.
2. Do not have sex with your family or kin.
This rule forbids incest or sexuality with one who is your mother, father, brother, sister and so on.
3. Do not have sex with one who has not yet reached puberty.
This forbids sexuality with a baby, child or one who is not physically fit for sex due to premature biological nature. If one is literaly born for sexuality due to biological nature however, then it is justified.