Responses
Judging by the art style, Seungho seemed like he was gonna. strangle Nakyum neck but was stopped by the servant, I guess it could be out of anger and shock
Seungho’s possessive characteristics, which relates to your idea of why he act coldly/violently due to the fear of abandonment.
But this case of figuring out if he’s going listen Nakyum or not, merely depends on if he’s gonna believe him or not.
I feel like he’s conflicted with his feelings for Nakyum and feelings of betrayal, whether he actually listen to Nakyum or his betrayal deluded thoughts ┗( T﹏T )┛

So y’all gotta understand Seungho probabaly deat with people leaving him a lot. When he’s finally let himself go to actually have feelings for someone, he disappears and he doesn’t know why.
like in the beginning of the chapter they don’t see other footprints so they assume that Nakyum was trying to get away from Seungho after he “confessed” to Nakyum. So honestly this would definitely hurt Seungho’s feelings too especially if he had brought down the walls. Can’t blame him for not listening honestly.
I think he’ll listen to Nakyum in the next chapter (hopefully he doesn’t pull an asshole move) because Seungho obviously still cares for Nakyum just like when he saw his body he was going to caress this face but retracted his hand.
He thinks that Nakyum left him so he obviously wouldn’t hug him.
I hope he listens to Nakyums story