UL takes place in the Dataverse (except the epilogue, revealing UL to be Lunadine Crimstaine's attempt to make a game while inebriated)...
Sureya is from Gehengard (I hope the spelling is correct, @Cibryll ), which is not featured in any XSP work currently...
I got the given name from a Turkish-translated-to-Afrikaans (maybe to English first) series... like how it sounds... "Sureya"...
I'm not too hot on the idea of Umbrageous Light being a video game made by a drunken Lunadine. However if you want it to be non-canon, you could have it take place in an alternate timeline where she breaks out of the Brainwashing Machine. Or if that doesn't work, you could make it work like Selenic Shadow where it's implied to be a dying dream of hers.