So... the great male taboo fantasy... Oddly enough, a lot of females share this fantasy too. Personally, I don't. Maybe because for most of my younger years I was an only child. Maybe because of things that have gone on in my family (not including myself). Maybe because I realise how illogical incest is, at least for myself.
For starters, I want to quote something which I said in a thread about incest on the forums I mod (as that was what inspired this post, not general musings on incest):
Mmkay, the reason it's frowned upon is quite simple. It's all down to the whole point of sex being conception. With society changing only recently into a position where sex for recreation is more or less completely accepted, the stigma still surrounds incest. When people are involving in incestuous relationships, you have to question their motives. In some people it can be a mask for a deepseated emotional problem that they feel requires sex with a family member. Not only that, but if it was acceptable, people would inbreed. You can't deny that the only contraception that is 100% effective is abstinence. All others DO fail. You can't guarantee that no children would be born at all, unless both parties were sterilised, which I think you'll find not many people would go in for, plus again, it would bring about the end of humans. As for allowing non-penetrative activities, I think we all know (those who are sexually active), that it's hard to just stop at that. You can't base a relationship on just that, without one or both parties being unfaithful because they desire penetrative sex.
So really, I can't see how it's beneficial for anyone involved. Like any relationship based on casual sex, it's rare that they work, sad to say.
My opinion is exactly that, an opinion. Based on my own preferences, as well as having a few facts thrown in to back up my beliefs. I've yet to find facts that refute the ones I have, or experienced situations to change my emotional perspective on this. However, show me otherwise, and I might rethink my position. I can understand why some people are incestuous to a degree, but I see it as they're unaware of all the consequences and are making uninformed choices due to lack of information or insuffcient psychatric counselling for the underlying issues behind their desire to partake in incest.