When Noctis died, he expected to- well- die. To fade away into nothing, destiny finished, world saved. Instead, he found himself trapped and confused in an endless Blue Void with a de-Scourged and equally confused Ardyn Izunia. With nothing else to do, they walked, and talked, and argued, and healed. Came to terms with each other and their fates.
Until suddenly they opened their eyes and found themselves disorientated, alive, ... and back in time.
It didn't get any less confusing from there, really.
- Part 1 of Nox-verse