Even though my focus right now is on pure fantasy, your work is so evocative that it makes me want to read through all the Locastus subs.
There are so many ways the mayhem these critters cause could bring about difficulties and misunderstandings, that they are sure-fire conduits to adventure.
This sounds like an item that a thief wouldn't want to boast about - I could see it making the rounds as each successive thief steals from the last. Probably why the thief was sitting alone.
I like this item and can see a few ways of using it in my own game.