this is O-D-C

this is O-D-C's ten foot pole

this is how far Im going to stand away from this thread.

Actually I think there is a psychological blockade to prevent incest but only if you grow up with someone. I have two half sisters. One shares the same mother the other shares the same father. 

I grew up with my mother and with one sister. She is very good looking. But I grew up with her and even though I know rationaly that she is pretty and we share just half the genes I feel absolutely not attrackted to her. 

I couple of years ago I  had first contact to my real father. So I visited him, I arrived at the airport and saw an extremly hot girl, after a couple of minutes I knew it was my other half sister.

I still have problems to see her as my sister. Its mainly due to the fact that I met her first time with 21 and see her once a year.

After having that experience I know that atleast if you share just one parent and dont know its your sister you could do her. Before that I thought there would be some kind of natural blockade like you wouldnt find her attractive.

Oni-Chan..

Nee-Chan..

^^^ If the above quotes are wrong.. I don't wanna be right. >: D

They can't be Nii-chan *and* Nee-chan, as both indicate older siblings. One of them has to be older, that's how your quote is wrong.

Oddly they use these cute nicknames for older siblings, but not younger ones. You don't hear imouto-chan or otouto-chan

Oddly, most hentai i've seen that claims to have incest always ends up being with adopted brothers/sisters or stepmothers or something like it. Even Hentai animators don't have the guts to do incest proper, and that shows just how taboo the idea is

Its taboo for a reason it damages the gen pool no other sexual perversion damages the genpool. If it would be allowed and not taboo and just a fracture of people would do it then it would cost Billions maybe even Trillions because we would have millions more handicapped people which wouldnt be able to contribute to the economy also a lot of recessive Illnessess would occure way more often like sicel cell anemia or cystic fybrosis. The cost for health insurane would explode also we would have to make more schools for mentaly handicapped the damage for the world would be extreme so its best its a taboo.

Thanks for correcting me.

I have readed hentai with blood-related parents and siblings (or at least what translators lead me to believe) so I don't think it's necessary taboo with some artists but incest is a theme that will be in hentai despite what we say here.

well i have cousins i'd love to Nail(i'm bold and honest). i'm not sure how to approach this one. we always talk about 2 consenting adults, but it seems more like mans law dictates our lives.

the fact that it's frowned a pone is understandable. why do your sister when you can do someone hotter? srry i'm out of words. i'll do this again later.

and there you have it.

I personally would never feel that way about any of my family, but I'm not against it either. If two people want to be with each other, why stop them?

Unless at least one of the people is infertal, you can never rule out procration.  How many times have you heard of a couple having an "accident" and 9 months later a new baby.  If this accident was to happen, it drasticly increases the chances of genatic defects.

There are other reasons why, but this is the most scientific one.