So originally, we infer Key as the Emperor was in love with Lia. I can see how, because Key was truly just wishing for someone to be kind and good, loving, to him so he could be real again (for putting in into this book "to be love is to be real" philosophy) but the irony here is that I think we're given reason to think Lia is a lesbian. Or at least completely uninterested in exploring any desire for men given how she describes their looks (in contrast to Marius who I think we can all agree is in love with the Cobra/Eric and very repressed or likely demi).
Now given what Key did for his adoptive father, I'm not saying he wouldn't lay waste to enemies, look for a way to resurrect Lia etc if she was like, his bestie (aka an equally strong platonic love) instead of his lover but I think we can all agree the og book and Rea herself said this was romantic attachment.
With that as baseline and from what we get of Lia's true personality and interests in LLE is that:
1. She is ambitious and talented and wants to do good for the people of Eyam.
2. For that she needs to be queen and she's willing to do whatever the king wants of her (as long as it fits her "good and pure" image) in order to have that power.
3. Despite the above, she's repulsed by men's attraction to her. Confirmation that she slept with Emer (so we know she likes women) and forgave her for the betrayal (and in the og saved Emer life even after she betrayed her to Rahela) implying attachment and attraction. Right now I'm assuming she's lesbian, aka exclusively attracted to other woman. We don't have her PoV so it can't be certain like with Emer but all the signs point to that.
So I think that what happened on the og was that Lia saw that Key responded to her kindness, and she used that accordingly and treated him well because as her guard she needed his loyalty; that he seemed ready to kill when she was stuck having to be perfectly sweet and defenseless would been a plus. And I bet she told him of her plans to do good for the poor and unnobled, and backed that with actions. Only that worked a little too well, and with the extended timeline they had more time to know each other.
(extended timeline bc it seems like Key went down voluntarily the dread ravine like a year or two after our canon. I have to reread all that part bc the confusion with Octavian is not helping >< Rae does say in the ending she fucked Key over bc he was older and more secure on himself on the og and he wasnt sent down as a corpse after dying for her and being betrayed)
So I think Lia saw where the wind was blowing once Key came back with the crown, fulfilling the profecy and completely willing to marry and adore her. And she said yes to being his Empress, but she wasn't ever in love with him which makes the Emperor reaction to losing her all that more painful. Poor Lia whose body becames literally what she hates most, an object for the Emperor to fixate in his grief and obsession regardless of her true feelings or ambitions.
Right now I'm thinking that both Lia and Key avoided a hellish future when Rae was sent to lady Rahela's body and derailed destiny, even if as of LLE ending it seems grim.
