I have found that, outside of his own three quests, Bastian is not a credible simulation of a normal person. His poor AI and out-of-context comments are just too bad. It's like he's deranged.
So, I've rolled a new Necro (called Libitina), and I'm going to treat Bastian as one of her combat pets.
This is them in the Wailing Prison:
Bastian's narrative runs as follows...
Libitina found herself sharing her cell in the Wailing Prison with another soul shriven - Bastian Hallix. A man of noble birth, prior to his death at the hands of Mannimarco he had been an Imperial Dragon Knight serving in the Blades. Libitina managed to fix him up a bit, channelling some extra animus into his depleted form (there were some as-yet-untapped skeletons in the cell for her to use). This strengthened and stabilised Bastian's body, but not his mind. Unfortunately, Bastian had already lost most of his memory. He also has a significant cognitive impairment. He’s incapable of realising that he is dead, has no real sense of purpose, and tends to just stand around looking like a stunned puppy unless he is given firm direction. Bastian has only a vague grip on reality, which is why his comments are so detached from what is actually going on around him. He frequently wanders off and gets lost while travelling, has trouble remembering what stairs are for, and sometimes gets completely flummoxed by simple problems like stepping over a puddle. Bastian is a sort of revenant, one small step up from being a zombie. Good enough to be the re-animated, persistent, tanky combat pet that Libitina needs to plug that very obvious gap in her Necromancer’s skillset.
The team:
Once Lyris has freed them from their cell, and they meet the Prophet, the story starts to become clear. It turns out that Bastian Hallix is the doom-driven, world-saving hero the Prophet foresaw in his reading of the scrolls. What the Prophet did not foresee was that Libitina would be acting as his puppet master. Libitina is there, on behalf of the Missing God, to ensure that Bastian fulfils his destiny come-what-may, no matter how many times it kills him. She is the dark fairy-godmother who will ensure that he does get to
the ball Heart’s Grief on time.
Libitina will not build positive rapport with her pet. Bastian’s guild skill lines will be advanced using a different player character. As far as Libitina’s story is concerned, all that business between Bastian and the Silvels just did not happen.
It is part of Bastian’s destiny to do the Thieves Guild and Dark Brotherhood questlines. That should be fun.