There seems to be a huge desire for triads... I don't know if it is so wise to go into this all with that notion. They are the most difficult configuration and yet the most often sought after. They most often end in one partner being hurt because love does not develop evenly. One gravitates to one or the other, usually the woman to a man and the other woman is left out and hurt.
If I were you both I would discuss just seeing what happens. There is no guarantee that the two of you even like the same kind of women. Why not go into this bonding on the fact that you would enjoy extra love in your life, rather than love from the same person. Why not embrace the possibility of meeting separate people rather than one person. Keep it all open and fluid to possibility.
I am thinking that you are thinking you want to do this together and that the above is not an option because you couldn't possibly be with someone without the other. Making an assumption about this as I have read it here many many times... if that is not the case, then so be it, but checking in to see how you both would feel if your journey were to separate you both would be good planning, because I am betting you it WILL come up. Better to deal with that now rather than when you are in it.
btw what you seem to be seeking is a unicorn. Do a search on this in tags as Neon says... I don't know what is in golden nuggets on unicorns, but if neon suggests a search there then I'm sure it is with goog reason. good luck
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