I'm interested in a what-if situation. What if the SS could during FO4 flirt with Deacon? Assume that 1) he's infatuated with the SS, but more in a reverent sense than a romantic one, 2) he doesn't see it coming (despite him being a people-reader) and 3) he can't reciprocate the SS's feelings (for emotional+job reasons). What would he feel? Would his world be turned upside down? Would the partnership be compromised? I'd love to see some eternal turmoil, but it's your call. : )
tl; dr: self-loathing workaholic married to his job is unable to take coworker flirting seriously because that would mean feeling feels, and feels are dangerous, so he bobs and weaves so coworker won’t quit.
ts;wr: We all know he’s unromanceable, and I’ve made the joke before that it’s because he’s married to the Railroad, but I think there’s more to that, and I think it dovetails into this conversation.
Deacon is unromanceable because there’s no one to romance. The person the Survivor meets has made himself a construct of the Railroad. He has crafted his existence entirely for the Railroad. There is nothing of him that another person could have or share that the Railroad doesn’t already claim. His face is for the Railroad, his name is for the Railroad, his waking hours are for the Railroad. Fuck, even finding the Sole Survivor is for the Railroad.
He has very little in the way of personal aspirations, goals, or desires (that he verbalizes to any great degree). I’m not saying this is good or healthy, it’s quite the opposite, but it’s effective for what he is and it’s where he’s at.
That’s not to say he has no personality (he has plenty of that) or free will, but he chooses, or feels compelled, to subsume his existence with the Railroad. He’s an ascetic of the Railroad.
Setting this idea as the foundation, there is nothing that could come between him and the Railroad. He’s given his face, his name, his time in service of the Railroad, why not his heart, too?
With all three of your conditions, I think Deacon would absolutely flirt back with no hesitation. Flirting can be pretty harmless, it can be playful, it can be fun, it doesn’t always necessarily lead to romance. He can deflect and avoid as long as he needs to, with humor, with sarcasm, with whatever he needs to keep the Survivor with the Railroad. This man is not comfortable in his own skin, because it’s one way he can avoid himself.
I don’t think he’d care much about how the scenario affects him personally as much as he cares how it’d affect the future of the Railroad. The Railroad needs the Survivor. Without them, the Railroad has no future and therefore Deacon has no future. His inner turmoil would probably not be focused on him, but how this scenario affects the Railroad. He, more or less, does not let himself have personal connections.
He makes no bones about the fact that he does not see himself as a good person, he doesn’t see himself on the same level as the Survivor. Deacon probably feels like he doesn’t deserve that kind of affection or attention, and is probably terrified of it at the same time. I’d imagine he feels like he deserves to be alone. He’s “everything that’s wrong with this whole fucking Commonwealth”, he separates the “honorable” Survivor from the rest of the “unhonorable” masses during his low-approval conversation, and includes himself with the unhonorable.
I think it’d be a big enough personal step to realize that he’s missing out on this kind of connection, much less how he’d feel about not being able to reciprocate.
Sorry, Nonny. I was out for most of the day and this was a tough nut to crack. I hope I answered it well enough!