Tawawa

And the demons of Goetia are from Fate/Grand Order, and since I'm the only one on the forum besides Revan who has played it, I had a huge advantage in guessing it.

They are used in many places, actually. It's a fairly popular topic, in certain circles. And Revan posted descriptions of some of the demons a few years ago in the off-topic section, before he started playing Fate/Grand Order. Or maybe they recently introduced a new character named after one of the demons, which gave you the idea?

When I was considering guessing (but gave up halfway through), by the way, I thought about mentioning "Demons" as the article you sent, because of the name of your demoness in Erathia.