darker than black

A monster of Khaira, where the people known as the Tezre live (a lizard humanoid)
This is a picture of one of their myths.

In the norther deserts of the new world they can be found. creatures of shadows. They come in the form of dead soldiers wearing a battle cape dyed in tezre blood (indigo). They wander the sands with a wooden lantern attached to their tails, which they use to attract their prey. At which point they steal your life force, and you become one of them.