I'm so glad you like them!

The descriptions are indeed the whole of their lore right now, but I can tell you a bit about how these items came to be in case you're interested in that sort of thing! I had wanted to draw a new set of items for the Wizard's shop, and thought something minion-based would be a good way to go about it. I try to keep his quest shop items centered around things like magic, Luna/kumos, the moon/night sky, and, of course, the Saherimos.

The Saherimos' Subetapedia entry says "The Saheric had a complex system of Sand Spirits whom they worshiped" and that opened the way to do something that hit a lot of themes I like to keep in mind! So a kumos-like sand spirit that changes form depending on whether it's day or not? It's the perfect fit for the Wizard's quest shop. (The bedtime story angle was 's suggestion and I thought it was the cutest thing ever.)

I like this Sand Spirit quite a lot, too, and wouldn't mind expanding on their lore with more quest shop items in the future. And maybe someday we can learn more about other Sand Spirits via non-quest shop places! :)