As far as summoned entities goes, Iedabeth isn't too dangerous to have around - at least not if she likes you.
She's a dark mysterious entity with a mostly calm but also playful side. She likes to play tricks on others, though the severity greatly depends on the person and how she feels about them. Most of the time it is harmless scares, which mostly involves turning any lightsource on and off, or having wax appear all around.
She likes horror, frights and is despite her mellow appearance a surprisingly teasing personality. When it comes to people she does not like however, she does not pull any punches in makign them feel haunted and unwelcomed.