What makes a party fun? These are just mere examples of how orgies are formed, and there are still lots of ways and reasons to do it.
The chaos that is seen in orgies is the only type of chaos that you would want to be in, because the more things that happen simultaneously throughout the whole sex party, the more happy and satisfied you are afterwards! Or maybe tie up your friends, and their friends who also love doing bondage? Have a foot fetish party with people who enjoy sucking and licking on feet just as you.
You can have sex with a girl, a guy, share and swap partners, and you can even do it in a group! But the main reason why parties are great is because of the people attending them.