Dexter: 10 Most Hated Episodes Of All Time

If no one ever mentioned Dexter and Debra weren't biological siblings, you would have never have guessed it by how close they were to each other throughout the show. Overcoming many arguments and fights, the brother-sister duo strengthened their bond with each passing season. Deb was also one of the first people Dex truly cared about.

Their closeness may have been awkward at times, but hardly anyone expected the twist season six built up to. Speaking to a psychiatrist, Deb rambled on about her relationship with Dexter, which 'The Doc' suggested might have been more than the typical brother-sister bond.

Sure, the two weren't related by blood, but the suggestion alone made longtime fans cringe. Perhaps stranger than the swerve itself, the shows' creators explained the pseudo-incestual storyline was in the works for quite some time. Two questions came from this reveal, and they were both "Why?"

Why did they ever think it might have been an OK idea? Exploring Deb's and her adopted brother's complex feelings would have been one thing, but teasing the idea of the siblings hooking up was a completely different animal.

Why did the idea take them so long? It popped up later (more on that to come), yet otherwise, it had no real value to the overall narrative. More than anything else, it gave fans an excuse as to why Deb didn't turn her Dexter in once she discovered he was a serial killer.