A love quadrangle is similar to a love triangle except that it involves four people instead of three. It is a complicated romantic situation where the parties involved may or may not be aware of each other. A common love quadrangle scenario involves a central object of affection who is being pursued by three suitors. Another common scenario is when members of a couple have affairs outside their relationship.
More About Love Quadrangle
A love quadrangle is a murky romantic situation that can cause hurt, at the very least. Emotional security is requisite of each party involved in the quadrangle. It is not for the faint-hearted. The kinder alternative is to remove any expectations of exclusivity and just agree on an open relationship.