That's a random question and very fun. My vote is for pyramid (with a triangular base, not the four-sided variety they have in Egypt) because the three corners in the base all are directly connected to the peak. In a square, if you designate one of the corners as the object of everyone's affection, then the opposite corner has to go through one of the other two corners (individuals) to get to the object of everyone's affection. I don't think that's quite the right model.

Cheers,
Michelle