Husband&Wife

husband and wife behind the giant snake

The Husband and Wife are seen on the bottom right walking away after the Giant Snake ate a man thrown over the railing by either a Deadite or Reaver. They're seen again on a monitor kissing in bloodshed, which indicates they're monsters.

Inspiration

Likely a reference to the Robeson family from The People Under the Stairs, a serial killer couple (and brother and sister) who keep their countless inbred children in their basement and kill anyone who discovers them.