Last year for this prompt, I did werewolves, this year I decided to interpret this more as ghosts or spirits.
I decided to do my design based off of a Ouija Board. A Ouija Board, or Spirit Board, is a flat board covered in letters, numbers, as well as certain words like "yes" "no" and "goodbye" and is used to contact spirits. This is done by placing your hands on the planchette and asking questions and the spirit would then move the planchette to answer.
When I was younger and we would use it at sleepovers, I would always be the one who moved the planchette and made my group of friends believe we were actually in contact with spirits.
On my pointer finger, I have painted a planchette with Serum No. 5 Day Glow. I painted a pentagram on my thumb and 666 on the rest of my fingers.
Here's a photo of the planchette in the dark :)