The Coal-Studded Ring

I've delved through old newspapers, through websites about the paranormal, and through reports of strange things involving light, fire, and heat. 

Apparently nobody calls Eris the Flickering Woman anymore. I haven't seen that name anywhere on the internet. And not everybody calls her Eris. There are tons of names she's called by.

The Burning Woman, the Obsidian Lady, the Warden, the Dancer in the Fire, the Firefly, the Lady of Light...

And not every appearance is the same. Sometimes she's seen holding chains in her hands. Other times she's seen as a firefly turning into a woman. There are also reports of an apparently normal woman jumping into flames and dancing in them, enticing others to join her only for them to burn to death...

In fact, I might've confused them for entirely separate entities if it weren't for each report mentioning the coal-studded ring. Every time, it's on the woman's right hand. That's definite proof that every one of these reports is about Eris.

In one report, somebody took the ring of of her hand and put it on. They started feeling a burning in their stomach and melted, right there on the spot...

And more than that,  sometimes Eris is portrayed as floating, hovering on a cushion of light and something more.