Day 26: Creepy shadow (Seth, post season 1)

Another almost-last-minute idea. This is what's happening to Seth during day 21: Foggy, while Kate's in the ballroom.

Seth gritted his teeth and hugged the wall, as he gently opened the door to what had once been Calvin Candie's study. At first glance, it seemed like there was nothing in the room but shadows - shadows that seemed to ripple the longer you looked at them.

He really, really hoped the consecrated iron rounds the ghost hunter wannabes gave him worked like they thought, because otherwise he might be shit out of luck. He never thought he'd come across something that scared him worse than culebras… but this ghost or whatever the fuck it was did just that. He knew how to kill one of them - stake or several bullets in the heart, take off the head, enough damage to break the spine and destroy the heart. Or fire, if you were desperate.

How the hell did you destroy something that didn't have a physical form?

One of not-Ghostbusters was sure that this wasn't a true ghost, but something that could slide into the physical body of whatever it killed, filling it up like water in a cup – which sounded like a shapeshifting culebras, but if what happened to that poor bastard in the garden proved anything, this was no bloodsucker. Whatever this thing sucked out from its prey, it was something that couldn't be seen.

Seth steadied his breathing, falling into the tracking mode he'd taught himself hunting.

One of the shadows coalesced, becoming more solid, and Seth brought the gun to bear.

If the bit about 'consecrated Iron rounds' sounds familiar, it's a reference to the Supernatural episode 'Hell house', where a particular religious symbol helps a ghost keep changing form as the internet rumours about it change. Dean and Sam finally destroy it when they themselves start the story that consecrated iron rounds will destroy the spirit.