Well, an elju, is a book for a Nonman, right? So, we have to assume that it's a keeper of his life/events, so to say. Doesn't Kosoter have to pull Cleric aside again and again to "remind" him? So, it's either a elju is a person/sranc that Nonman continuously have with them since the womb plague when the began to go Erratic. And, their "deeds" are passed from one elju to the next. Or, an elju is simply there to remind the Nonman what it's purpose is when that Nonman has a mission to carry out. I'd say the former is much more likely, imho.