a kin is a character (or characters, you can have more than one kin) you associate/identify with. kins are to help you express yourself, comfort you etc.
A large community generally centered around "relating" to a character one way or another, also the act of doing so. Essentially, after looking at a character and identifying with or as them, the definitions split.
1. Coping; many people kin characters to cope with their situation or illness.
2. Reincarnation; others believe in the Multiverse Theory and when someone dies, their soul may hop between universes.
3. Just for fun; kinning isn't that serious, so some may identify with characters for the fun of it.
2.) Liking or relating to a (usually fictional) character so much that one integrates thr character's behavior, style, and (in some cases) physical features. Often seen in role-playing communities and on tumblr
1.) "Why's that guy dressed like that?" "Oh, he's kin."
2.) "You know, you act so much like *insert character*." "Yeah, 'cause I kin them!"
A shorter version of kinfolk; meaning one's family. Someone who is connected to you by blood or marriage, i.e. your kinsman, kinswoman, kindred, relation, relative.