Charm Changers

More akin to a spirit than an animal, Charm Changers nonetheless have a special place in these Fantastic Lands. With their intense curiosity and the near limitless variety, Charm Changers can be found in any place so long as magic exists there.
In their base form, they resemble wisps of pink, yellow, and orange light, sometimes looking like a human child, sometimes no more than an amorphous blob with two round eyes. They are very pure beings, and have an intense attraction towards materials used in spell-casting with a particular regard for books and scrolls. As such, Charm Changers have been revered as guardians of magic shops, libraries, and rune spots alike.
Visitors and creators of such places would be wise to leave a small offering of some sort to the Charm Changers, usually consisting of a story, a carving, or a runestone. Charm Changers will take such offerings and turn them into a vessel for themselves, thereby adding the offering's magical power to its own, and providing itself better protection for an otherwise delicate body. Those who keep Charm Changers happy are blessed with prosperity; once appeased, Charm Changers are more than happy to assist those who visit or work in the place they inhabit.
However, Charm Changers can be corrupted with offerings of dark subject matter, as well as being forgotten or neglected. Charm Changers that suffer such treatment will become "Cursed" Changers, and turn otherwise benevolent places into areas of ill fortune and disease. Cursed Changers are black, green, and silver as opposed to their lighter counterparts, and once transformed, are impossible to change back. The most tragic incident of Charm Changers turned Cursed occurred at the Library of Nott, where an offering of contaminated elixirs turned nearly two hundred Charm Changers into maddened spirits that began to leak poison into the streets. The dragons were forced to burn down the entire library, incinerating the Charm Changers, along with hundreds of scripts and books.