There is a specific human behavior that is a large factor of why I'm open. In short, it is that moment when a very good friend of mine will give me the "speech" about how I can't hang out with them anymore because their "significant other" isn't comfortable with it. This has happened to me whether or not the very good friend and myself have any type of sexual relationship. People enter the "relationship" and then I have to go away.
When I started thinking of how I wanted to conduct my own "relationships," I decided it was bullshit to try and tell the person I was going to be with who they could or could not hang out with. I mean, saying, "hey, that person who has all the human body parts stacked in their freezer? Maybe not the best person to spend your weekends with" is very different than just saying, "that super cool person who you have lots of fun with? They make me feel threatened, and therefore I need them to go away."
That's the first seed of jealousy, isn't it? Not, "you fucked that other person and now I'm angry." More, "you spent some time laughing and smiling with that other person. And that's something that I feel only I should get from you."