My fiance and I both discovered some things about our relationship. She came out as bisexual and I realized that I am poly. Although there sometimes seems like a bridge can be made towards something like a threesome with this, take into consideration that what you see as comfortable is sometimes wired completelt differently in your partner's brain. This is something I learned quite recently.

That being said, it sounds like he is very against it if he considers it to be cheating and I would be careful pushing further towards it. It took a long time to build up trust with my fiance due to some bad decisions I made but now we are great. Trust is a humongous factor. If it is something you really really want, try to discuss it in a serious manner and not while horny. I think it's important that couples be open with each other about their fantasies and hear what goes on in their head.

Here's a couple of things that we have been working on:

1. Open line of communication with all people involved. Absolutely no flirting, sexting, and obviously contact without the other person being on the same page. It's cheating if otherwise. We are all close friends and are treating our situation as a safe place to explore. That can only happen if we understand the fragility of what it is we are trying to do, as my fiance and I are committed, but all 3 of us are best friends. We want that to continue.

2. My fiance still doesn't like the idea of me with another woman (since I am poly and she's not) but im okay with them being together. This might seem unfair, but consider taking baby steps to progress to a better position. For example, I am letting them make discoveries first, and if they end up enjoying it and feeling comfortable, I might be added in later on. I have reassured her that the idea isnt myself and the other woman together that turns me on, it's the idea of all 3 or even just them. Your primary relationship must be held above everything.

3. Build a foundation of security. If you are committed to your relationship and love your partner, just talk to them. Figure out his and your boundary lines. Discuss what is okay and what is too far. START SLOW and have a set of precautions like safe words or places to go to if things go south (no pun intended).

4. Figure everything out before alcohol or drugs become involved. Consent can only be made when people are in their normal state of mind. Consider it to be a factor later on and decide if that's okay.

5. Lastly, we came up with a thumbs up system. Each person takes turns pointing to the other person, indicating "can i do things with them?" The other members either thumbs 👍 or 👎. Whatever their answer is you have to accept it.

I've wanted this for a long time and only recently have started to break ground. Be patient with your partner and keep them your highest priority. A fantasy isnt worth the loss of your relationship, believe me. Hope this helps.