Hi @v3llichor! Thanks for reading & I love your thoughts. I also recognized that neck-adjacent trauma in Aziraphale and had a similar impression re: the open collar. I think though that they did give us enough here that we can see from where that trauma came for Aziraphale. I'll show you my take on it, in case you're interested. Just a warning: this is potentially triggering stuff. Mention of sexual abuse & self-harm.
In S3, they take the vibes we got from The Metatron and the situation with these angels in Heaven and make it a bit more direct in having Michael talk about how The Metatron used to "fiddle" with the book. Books are people and "fiddling" is the among most common molestation euphemisms in English. Having Michael say all this while having a breakdown while The Metatron literally haunts her thoughts? Having her voice it all to Crowley-- a rape survivor? That was making it clear that The Metatron is a sexual predator.
What this has to do with Aziraphale/"Asa" and his open collar situation is that Michael being abused by The Metatron means that others were, too-- as there's never, ever just one victim. The story is paralleling the intimate partner violence story that is Lucifer's abuse of Crowley with the abuse scandals in churches and cults-- Heaven and Hell as two sides of the same evil coin. It's very much a Pratchett-y condemnation of all organized religion and the like and the harm they can do.
Telling us that Michael is a sexual abuse survivor is also telling us that some of the other angels Up there also had their books fiddled with without their consent. This is when we have to get into the fact that, Aziraphale's Nightmare or not? The contents of The Book of Life that Michael is carrying around-- the *literal* book that she says that The Metatron used to fiddle with? It all comes down to Aziraphale's life.
In the end, Michael is there with book pages for sushi and rubber ducks and Whickber Street. The Book of Life is a book of Aziraphale's life-- the story to me seems to be very much saying that The Metatron preyed on Aziraphale.
It's very much there in aspects of Aziraphale's character all along and it's also there in Gabriel, whom I've thought was "an unlucky choir boy" since I first saw 1.01. Gabriel is the most misunderstood character in this story, imho, and not responsible for that neck violence, but I don't want to go too far away from the topic of the necklace.
It seems most likely to me that Aziraphale being so exact about his appearance-- always straightening the collar and the waistcoat, always wearing something, as you pointed out, around his neck? That is an attempt at feeling in control of himself. It is rape-related trauma-adjacent behavior, not so dissimilar to a lot of Crowley's control-seeking behavior. I think Aziraphale's aversion to having people around his neck is because The Metatron choked him.
This would especially go along with how, as you pointed out, one of the scenes where the neck thing comes up is 1793 and that scene is already full of paralleling subject matter to this. Jean-Claude was a rape-y creep, Crowley's own trauma was triggered from what was happening when he arrived, etc..
This is actually why Asa's open collar was eerie to me. Not the flagging the non-binary yellow with the necklace-- that wouldn't be eerie, just awesome! 😊-- but the fact that his collar was so open in this scene was unnerving because of the circumstances. The show makes the bookshop metaphorically Aziraphale and then has it owned by another, just as eerie version of Aziraphale's abuser... and "Asa" trapped in all of it, with his shirt open and his neck exposed. Like the whole place wasn't creepy enough lol.
Whether or not you think this was Aziraphale's Nightmare, we know that it would be his nightmare in general to have that open a collar around The Metatron. There's both a vulnerability to the open collar and a sexiness to it that Aziraphale obviously wouldn't have an issue with around Crowley but which would make his skin crawl if he were to be that exposed around his abuser.
When we have an Aziraphale who is all buttoned up as a means of control over his appearance shedding layers around characters like Crowley and Gabriel, it shows us that he trusts them. All of that adds layers to how it's then disturbing when we see him vulnerable in a way he wouldn't wish to be around someone he does not trust and who has done him harm in The Derektron.
I'm not so sure that the idea is that that Asa has not suffered the same type of neck-related trauma. It's possible that he has not but there is some kind of physical and/or sexual abuse that has happened to him and the situation with Derek did not seem especially healthy. For one thing, it's established that Asa has worked in the bookshop for years but it's like he can't go into the back room without Derek's permission. He has to pretend he doesn't really know where stuff is and ask Derek for help, even though he appears to be the one doing all the work. This situation is humiliating, right?
Asa's a full-grown person capable of bookselling and the shop is the size of a closet. Even if it was only his second day on the job, he could probably figure out where the books on astrophysics were lol and manage to sell one. But it's like he's got to default to Derek with every customer that comes in so that Derek is always the one in the know and in control-- all of which leaves Asa looking dense to the customers. Derek is taking pleasure in Asa's humiliation.
What makes the situation even more painful and horrifying to watch is that we know that this is a version of Aziraphale and he's completely out of control when it comes to *books* and in *a bookshop*... it's the total opposite of Aziraphale literally designing his bookshop and building and running his own businesses. The nightmare for Aziraphale here is that he had made such a mistake that, ultimately, he didn't fully claim ownership over his own life the way he wants to and the eternity for him instead was Derek's Bookshop-- all of infinite time with himself and his life not truly belonging to him.
This Derek and Asa dynamic is really a bit what Professor Anthony was trying to feel out during the date in The Bizarro Dirty Donkey. "Um, so, the bookshop?" was basically "what is the deal there, as that got a bit weird?" and Asa's reply is to start with how Derek is the owner. That's all we needed to hear, really, because that's the whole of it. Maybe Asa's trying to hang in there thinking that he'll get the bookshop when Derek dies (I doubt he will lol) but it's a life lacking in the dignity that Aziraphale has always brought to his own.
There's something else about the open collar situation that I think might be worth a look. There is a cluster of four of what looks like pin pricks on the side of his neck, in a spot that might normally be covered up by the collar. There is suggestion already in the story that Aziraphale has been known to inflict self-harm when under stress. There are two scenes that show him doing what is one of the most common examples of that, which is picking at his nails.
In S2, when Aziraphale held up the drawing of Gabriel to the bartender in The Resurrectionist, we saw Aziraphale's hands close up and the area around his nails on his non-dominate hand were pretty battered and swollen, including one that was openly infected. Near the end of the Job minisode, when we saw Aziraphale alone on the beach, he was holding and moving his hands in a way that suggested he was subtly harming himself, stopping when Crowley approached.
The 'dancing on the head of a pin' story with the pin/pen/plume happening everywhere, especially in S3, including self-harm by way of pin would not be that surprising. Whatever is going on with Asa doesn't seem like it's all that far off from some of Aziraphale's struggles. (One way to interpret Asa, actually, is that he *is* Aziraphale, as there is evidence there to suggest that, whether or not you think it's a dream, Asa is just an Aziraphale who remembers Crowley, which is why he and the Professor are companionable enough but ultimately not that happy, as their final moments showed.)
Crowley's chain necklace that you brought up, too-- I think that's a good parallel, as from what we can tell that is related to Hell and Lucifer. It's why he stops wearing it after S1 (and why he took off his 'tied knot' bolo tie from Aziraphale when he reported in to Hell in S1, imo.) Another suggestion of this is Brian Cameron's chain bracelet-- Cameron being one of the many faces of Lucifer, one primarily there to discuss the aspect of The Devil that is Lucifer's abuse of Crowley.
