octuple-fourth-cousin
A person who has no parents, no grandparents, no great-grandparents, no great-great-grandparents, and sixteen great-great-great-grandparents in common with you. You're related, but you're also completely lost in the family tree.
My octuple-fourth-cousin showed up at the funeral and asked if I was related. I said, 'Yes, but not by much.'
My octuple-fourth-cousin called me and said, 'We’re related. Why don’t you ever call me?' I said, 'Because you're my octuple-fourth-cousin. That’s a real thing, but it’s not a good one.'
My octuple-fourth-cousin texted me: 'We’re related. Why do you ignore me?' I said, 'Because I’m not your best friend. I’m just your octuple-fourth-cousin.'