My understanding from the novel was more... lust based at this point. He likes the emperor in the physical way, the he stopped me falling to my death, he's powerful and hot ways. All the basic shiz. He can't really help that he's attracted in that way. Now the love aspect doesn't make sense to me until the next phase when he goes back. He doesn't go back to the palace or even tell garon he's there. He moves back to the mountain, the old village and garon finds him there. Visits and they take things slower and eventually he is convinced back to the palace after garon is just, nice to him. He stops the murder sprees and just tries to be good basically.
Yeah, also in the novel, though he did exactly this, wanting to stay with raon, they weren't really explicitly in a relationship, they weren't kissing or together really, from my memory. So not having that level of relationship with raon made is less muddy and weird that he would still choose the emperor. It feels a cope out to say it felt more realistic in the novel but it really did.
I agree it feels rushed and doesn't make sense. We were in the village with raon and roha for chapters! Anyway, it's defiantly fallen off towards the end. Like whoever is writing this version is bored and just wants to be done.

Trauma bonding happens. I care that author didn’t bother to explain why. Why does Roha miss him? What part of Garon does he crave? What flipped his feelings so hard? A single sentence of insight would’ve been enough. Right now it just looks like author is sprinting to the finish line and tossing logic out the window.