A term that implies incest.

When you and one of your siblings says or does something with each other that seems incestuous like Jamie and Cersei Lannister from Game of Thrones would do - i.e. accidentally checking out your brother's ass from afar even if you didn't realize it was your brother or getting caught making out with them all Eurotrip style.
Brother: When I get there you gotta give me that booty!
Sister: Uhhh, that was a little to Lannistery for my taste....
Brother: No, I mean the money you owe me!
Sister: What are we, pirates?
by MoonWolf June 6, 2014
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