>>65287204she has a ton of in depth lore in her original songs and earlier cover songs that go into topics about her as a multiverse creator/destroyer
her 2nd anniversary hoodie that you can still preorder here
https://shop.hololivepro.com/en/products/la-darknesss_an2nd and the original official art
https://twitter.com/gishiki_unc/status/1728749201297752424/photo/1 is about her using a fragment of her power to summon spirits from the void and her holding the star of eden in her hands while her arms are wreathed in obsidian flame
and no matter what thing you take as being canon or not if you go by the officially released manga shes at least hundreds of millions of years old according to lui who has only known her for a few thousand years which makes lui at least that old too which is pretty cool