Polyamory, which is different from polygamy is defined as being in romantic and/or sexual relationship(s) involving 3 or more people with the consent of everyone involved. That may seem complicated, but it's not too hard to understand. There's no set way for a polyamorous relationship to be. I like to separate poly relationships into two categories. One of those categories is poly relationships that involve all people in the relationship dating eachother. The second category is poly relationships that involve multiple poly people dating other poly people without all of them being connected. An example of this would be if Person A was dating Person B and Person C but Person B was only dating Person A and Person D which doesn't include Person C. Poly relationships can also fall into both of these categories. Like I said, there is no set way for a poly relationship to be. The only rule is that consent must be involved. Just to be clear, there is a massive difference between polyamory and cheating. Polyamory involved communication and everyone's consent while cheating does not involve consent. Communication is very important in poly relationships to make sure that everyone is comfortable. Boundaries should be set and everyone should be able to inform others when something bothers them.