Group

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A group is a group of system members within a system or sisasystem that stick together and spend time with each other, sometimes almost exclusively. They may often front together, and they might live together or near each other in headspace.

It can also serve as an umbrella term for any situation of multiple headmates being more closely connected to each other or more cut off from the rest of the system, including sisasystems.

Related Terms
Clusters are groups of headmates who are grouped together based off some sort of similarity.