I recently did Zerith-var's quest for the first time, and I like that it makes it clear he's not a typical necromancer and has a very different view on life and death to most of them (although I would also like a classic necromancer companion at some point) but I kept thinking the quest is quite one-sided. He's telling us all about his views and how he uses necromancy to convince us to trust him while we're just standing there, technically sort-of undead and almost certainly going to die and immediately come back to life in front of him at some point and just staying quiet about it all. I know the Vestige almost never talks about themselves (so they can be a blank slate for how we imagine our characters behaving) but in this case I wish ZOS had made an exception because I'd love to know what he thinks of them being the Vestige.

My immediate thought is it goes totally against everything he stands for. Most people in Tamriel would probably classify the Vestige as some sort of undead, and the more informed view is they're some sort of daedra, or at least daedric hybrid. Depending on how far through the main quest you are they may or may not have their soul back.

But I also think he could be persuaded to see them as at least an exception. They didn't choose this, they weren't corrupted or recruited, they were simply murdered and sacrificed to Molag Bal and then managed to break out of prison, escape Coldharbour and eventually to fight their way back in to Coldharbour to defeat Molag Bal and take back their soul. Along the way they learned to use the abilities that resulted from their new status to their advantage, which doesn't seem that different to learning to use necromancy to free trapped and corrupted souls instead of controlling them.