What’s the difference between ID and kin? Do you choose your ID?
The problem with “ID” as a term is that it doesn’t have a set definition and means different things to different people.
Some people who are kin use “ID” to mean what they consider their primary kintype, the one they feel closest to in this life/world.
Some people who are not kin use the term “ID” to mean someone they feel a lot like and wish to identify with/be known to be similar to.
Some people who completely misunderstand kin use the term “ID” to mean ‘more real than being kin’, which is not a thing.
http://fromfiction.tumblr.com/post/146197494047/what-does-it-mean-to-id-as-a-character-do-you