This is my demon.
I am unsure who she was in life, although I suspect she was an artistic type, a repository of knowledge, perhaps a member of some cosmic clergy. I am unable to pronounce her name, although “Methaniel” comes to mind. She seldom speaks, having no mouth or discernible facial features. Her head is a lantern, a cage with a single glowing “eye” inside. The light from this eye can change color, and the demon communicates by creating light patterns along the wall. Her body is made of some metallic substance that shifts to and fro. Her “heart” is exposed through a hole in her chest and has the same properties as her “eye”.
She sometimes carries a net made of some silver material. Odd things get caught in them. In her presence, objects tend to gain hole or net patterns. I use these objects as artistic inspiration.
I originally contracted with her to gain knowledge of the universe beyond human understanding. In exchange, I feel the urge to draw pictures with holes. Many many holes.
She is summoned by lighting up a incense inside a censer in the shape of a lantern plant and emerges from the smoke, or through creating a series of small holes in the wall which become a portal.