I suggest that you do some reading around here to establish yourself with what *usually* *might* *could* happen in your new endeavour. There are a lot of threads that have come before that could help. Try doing a tag search on "vees" "triads" "secondaries" and see what pops up.
It sounds like you are looking for a "vee" situation rather than a triad as it doesn't sound like you are particularly welcoming another partner in.... If I were you I would just see how everything transpires and not push any kind of agenda. Having an idea is a good idea but then just letting the fluidity of the moment happen when you find someone seems to work best.
There is a few threads that might help you build on a foundation and help you get a grasp of what you value in relationships. You might find it helpful to hear what other people have learned also and what their stories are... try a tag search for "foundations" and "lessons" and have a look at the blog section.
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