When hubby and I were in our 40s we began attending meetings of groups of couples of our age, mainly in private parties where the rules were the same as in swingers' encounters. It was safe and funny and many times we used to invite my brother and wife to go with us. We four had great familiarity and in our first years of marriage often we had some funny pranks after dinner at home, like games in which each had sex with the respective spouse on the same bed or side by side on the carpet in the living room. We were totally at ease getting naked and doing such pranks but we never got into an incestuous affair, I never even got the will or the curiosity to try it, and I have no doubts that my brother's thoughts were identical.
At that time we were young but even in maturity our behaviour didn't change, and actually I've to say that my brother never was the kind of man that makes me horny. He's younger than me, during our childhood I was who gave the orders and till now I look at him like a little brat and still boring, and having sex with him was unthinkable thing for me. I believe that consensual sex among adult relatives − and just in this case − is quite acceptable, but this is a theoretical view and as for me I never got concerned about this possibility, and I'm sure that it was the same with my brother. Many psychologists follow the assumptions of the Westermarck Effect and maintain that familiarity among relatives rather than a stimulus constitutes a barrier to sex, and I completely agree with this point of view. How could I have a fuck with the bastard who in our childhood often stole my piece of pie and ran so as not to take a slap?
In my own understanding there is a clear distinction between sex and familiarity. Supposedly healthy sex presupposes familiarity, but the familiarity does not necessarily lead to sex even when it involves things like daring caresses. Actually, during those recent encounters of group sex it was common meeting my brother alone and a little despondent, and saying that I would prepare him to have a fuck "with one of these bitches around" I used put my hand under his sarong to grab his dick and give him a hand job. He always left until he was completely hard and then walked away to have a fuck with any female that was available.
Once we both were a little drunk and as he wasn't getting an erection I offered him a blowjob. I was joking, but surprisingly he laughed and said "If you want..." It was a kind of challenge, so I thought "Fuck it" and there I was sucking my brother's mast and feeling not more than a little shameless. Soon he was ready to a fuck and then went away to do it with the first available woman he could find, and I went to other side laughing at what I had done. From then on he sometimes asked for a sisterly "oral support" during a party and I never refused, though I always thought and said him that if I was not a loving sister I'd never do the job of preparing him to have sex with other woman. Receiving a blowjob from me was very normal for him, maybe because I used do it naturally, but if I asked for a lick I'm sure he would refuse and indeed he never touched me in any intimate part not even my thighs.
There are controversies about what is incest, and some lines of thought maintain that oral and anal sex aren't incest because both don't involve risks of reproduction. As for me sex is sex no matter the way it's done but I believe that oral caresses with no consequences such as orgasms or a sexual intercourse to follow aren't sex. So I was totally at ease doing those daring caresses on my brother's dick and moreover I never noticed that he could want more than a cosy blowjob from his sister. If I thought he wanted sex with me he would get a slap instead of a sucking.
Besides this clear disinterest of both in having real sex among us my brother always warned me when he would go into a dark room to avoid meeting me there. At those private parties the dark rooms weren't the same as the ones found in public places, being smaller and subjected to rules to allow to those participants the thrill of never knowing who their partner was. Well, I wasn't concerned about the possibility of being fucked by my brother without knowing, thus I never paid much attention to his warnings and also I never bothered to tell him when I intended to go there. I went to those parties for fun and not to get worried on where he could be every moment, so I wasn't much careful when going into a dark room, and if brother was there what would be the problem?
He would be one among several, in such environment the partners are anonymous and a dick is a dick as a pussy is a pussy no matter from whom they belong, and if eventually he was one that fucked me none of us would realize that we had done a forbidden thing, so it would be like if nothing bad had happened. As I had read somewhere, if you aren't aware that you're doing a sin, you aren't doing a sin. Both my brother and I would never do it consciously, the difference was that he was worried with the possibility of things happening in the dark without our knowing while for me the risk of getting into an "unaware incest" was nothing to worry about, as with no awareness there isn't incest.
I can admit that after several group encounters probably I had been fucked by my brother, that is because he often went into the dark rooms and I also went too though never warning him that I would be there. Although these rooms admit a few people, in such complete darkness and without telltale words or any other sign that could allow identification I never knew exactly who were the others, so for a mere matter of chances I could say that I "probably" had practiced incest without knowing and that never bothered me one bit. If it happened, it happened, so what? My only response was to tell a lie a few times when my brother asked me if I had been there, because I didn't want him to be worried about the possibility of having had me inside those rooms while he was there.