Andrew and Ashley Graves Redraws - The Coffin of Martin and Diana

Ahh, seeing this show takes me back. Dealing with demons wouldn't be out of their usual jurisdiction of horror, and since they're stepsiblings, there's technically nothing incestuous between them. Though the cannibalism might push things beyond their tolerance.

Fun fact: In the comic that this show was based off of, these two were a couple.

Make use of that knowledge however you wish.