Thinking back to the idea that @amberdickie made about the emperors after New Life being in a world like Spiritfarer, like they all look like a mix of their lives (with new and afterlife being only their first ones) but still somewhat themselves, having glowing eyes and they all have their memories of many lives and they get to be together before they start to feel weak and they eventually pass on.
I think personally Shelby and Pix would be the last to pass on, Pix going before Shelby though. He served enough he is ready to pass on. Even if Shelby was already weak she wanted to see everyone before they passed because she never got to say a proper goodbye before. So when she is really the last once again this time she doesn't resort to suicide but Pearl to take her safely to rest.