Important Lore Personal NPC's

[Tio Silver]

Are players allowed to request a personal NPC whose backstory ties into wider site lore?

For example would it be acceptable to request an NPC who was responsible for the death of Vri's wife; the mother of Jesine and Kielik?

[Pig Boy]

But while Jesine aged normally until adulthood, it quickly became apparent that she had inherited her fathers immortality. In time, despite the eternal youth of her family, Anaza was aged, weak, and dying. It was Pier & Pre who bestowed judgment on Anaza that her time had come and, quite painfully, Vri allowed death to take her.

I assume you were using this example as a hypothetical since it sounds to me like she died of natural causes, not foul play.

I'm not sure about any other important lore characters, but it would have to pass Lore Analysis most likely if it was permissible, just to make sure you've got the lore understood in order to ensure consistency of lore.