Allow Us To Explain
So we decided to do a grid about incest, because who doesn't love incest? ...Okay, everybody. Everybody doesn't love incest. But first, let's take a time out for a helpful vocabulary lesson: What squick means. Now that we have sufficiently educated everybody who didn't gleefully, purposefully seek out and devour bad fanfiction when they were teenagers, we can get back to our point. Despite incest being one of the most universal* cultural taboos in world history (right up there with cannibalism!), we sure like incest in our fiction. In folklore, where the Greek and Egyptian pantheons are founded on incestuous couples, and incestuously romantic or born heroes abound, not to mention all the examples (or near examples) from the Bible. And we like to put it in our popular culture as well! Sometimes we're subtle or wishy washy about it, sometimes it's a great big squickfest, but these are our favorites because we find them fascinating. We'd like to thank our runners up, Revolutionary Girl Utena (disqualified not because it doesn't totally have incest in it like ALL the time, but because we put RGU on almost every power grid), Veronica Mars (because wow, that was complicated), Back to the Future, and Quicksilver and Scarlet Witch. *I said "most universal," so as to imply that it's not entirely universal. As with all taboos (including, again, cannibalism) there are exceptions.