Disclaimer: Only adults have sex here. Nothing to get freaked over. This is a semi-serious essay, I hope.
***** WHAT IS INCEST? *****
Do you go to family gatherings
looking for fuck-partners?
MOTHERFUCKER!
Well, that is one way to start.
It is pretty common in Russian to say
"YΓ³b tvoyΓΊ mat"
, meaning "Really?!" or "Gosh!" But literally it is "(I) fucked your mother" and serves as an emphatic exclamation. "What, you can't pay me yet? Fuck your mother!" "Oh no, the team lost again, fuck your mother!" "What a babe, fuck your mother!" "The bus never even slowed down for me, fuck your mother."
This does not go over too well in the Anglophone world.
Who was the first motherfucker? Probably not Oedipus. Human sons (and daughters) have been fucking their parents, and vice-versa, for a long long time. Those kids have been fucking each other too, and uncles, aunts, grandparents, cousins, all one big happy horny family fuckfest, right?
Yeah, lots of Mommy-fucking and Daddy-sucking and sister-swapping, right?
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Wait. Let us start over.
Just what the fuck IS incest? Alas, like True Religion, there is no simple answer. The biology is pretty simple but still ambiguous: If you have sex with someone whom you share a certain quantity of DNA, it is genetic incest.
But what is the critical ratio of DNA? And what does "having sex" mean?
DNA first. It's called consanguinity, or "with the blood", even though literal blood has nothing to do with it. The Anglish language is a bit archaic, hey?
Anyway, we measure degrees of consanguinity. (I will omit double-cousins and similar rarities.) Your identical twin or clone has the same DNA as you -- zero degree, no separation. Your parents, children, and full siblings have 1/2 of your DNA -- first degree. Your blood uncles, aunts, grandparents, and grandchildren have 1/4 of your DNA -- second degree. Your blood first cousins have 1/8 of your DNA -- third degree. Other blood cousins have even smaller proportions.
(My partner's parents are second cousins. Their great-grandfather said their kids would be morons with tails. He was wrong. Whew.)
Some say fucking relatives is not incest unless pregnancy is possible, penis in vagina (PIV) -- a strict Bill Clinton definition of "having sex" -- and is discouraged because of possible birth defects. What are those chances?
Fucking your clone or identical twin will not have much effect unless one of you undergoes some serious XY-chromosomal tinkering. Mating with parents, children, or siblings DOES likely have serious birth defect risks -- but good hard data is lacking. Figure a risk between about 10% to 30% above the general population. For first cousins the risk is in the range of 1.5-3%.
Now we hit ambiguity. First-degree fucking is generally verboton. But cousin or uncle-niece mating is common or even expected in much of the world -- in some places, up to 60% of all marriages! Genetic incest in one place is not considered such elsewhere. Some cultures ban sex within the clan or moiety where any shared DNA is vanishingly small; other cultures insist on it.
Do you prefer a culture where you cannot marry your cousin or uncle, or one where you must, or one where you have an option?
Family can have a lot of sweaty fun if only PIV baby-making sex is 'incest'. Stick with oral or manual gratification; squirt the semen soup into a mouth or anus or armpit or empty eye socket. First base, second base, third base -- safe!
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