what you are going to offer him is called a "triad." I suggest that you do a search in the tags for "triad" and "vee" to see the difference, because it sound like you are really offering him a vee... with you being the hinge...
The situation you are describing is the best place to start a poly dynamic. Friends first and a movement to more often seems to work best. Good luck, and ya, in person is best I think. Why not start communication off right.
I also suggest you look at tags like "lessons" and "foundation" to get an idea how you might start off on the right foot.
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