Kindating is when you datesomeone based on your and/or their kins. Especially if the kins are commonly shipped and/or in a canon relationship.
"Did you hear? Alex started datingSam because Sam kins Crona and Alex kins Maka."
"Oh, that's interesting. Do you know why?"
"Yeah, Alex kindates. They like dating people based on their kins."
"Oh, that's what kindating means. I didn't know. Thank you."