Lemur

A Lemur is an evil shade. First seen in Ghost Story.

Description
Lemurs are shades that have given themselves over to malice and rage. They don't know pity or restraint or fear.

Appearance
Harry describes them as dark, slithering shapes. They looked vaguely like they were cloaked in dark robes. They moved amongst the Wraiths with them like sharks after blood.

In the Series
In Ghost Story, they attack Mortimer Lindquist's house bringing wraiths with them as their attack dogs. A group or three lemurs attack Harry's ghost taking chunks out of him and consuming them until Butters and Bob come along.