Ruby's undead ancestor stalking her
Made of stone. Blurs in sight when moving, but seems capable of moving at high speed. Seems to be able to disappear.
Is stalking Ruby for currently unknown reasons. A man claiming to be named John has told Ruby that she used to be a friend of his but has been taken over by a demon. The demon seems particularly resistant to death, but John and his friends had a device to help with this which has since been lost.