He's doing it for the sake of Dong-hyuk, he's lying in order to separate and drive Yule away from Dong-hyuk. Kyungsoo still likes Dong-hyuk (not too sure how much but he does) and that's why he feels it's his fault that Yule got involved with Dong-hyuk, so he's trying to lie his way back to Yule and save Dong-hyuk.
If anything, i think Kyungsoo needs to make it clear to Dong-hyuk, but i get the reason he can't tell him his intentions. If he does, the Dong-hyuk would continue to try and save him, but it will only bring him more pain.
I can understand why you are a bit confused, it's a roller-coaster for me too, but i think i got the handle on it.
Also hope this makes it a bit clearer for you, if not feel free to ask.
To me it seems it's a bit of both. I think he's lying to protect Dong Hyuk because he loves him and found happiness with him but at the same time I'm not sure he could live without Yule... I feel like a part of him will always want to be with him no matter how dysfunctional the relationship is. Just my interpretation tho
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I'm not sure if Kyungsoo really can't live without Yule, or if he says that to protect Donghyuk... Last Chapter I thought he wanted to go back to Yule to protect Donghyuk... the Chapter before that, I thought he wanted to go back to Yule because he really can't live without him... what is it now? what do you all think? :D I'm confused and would really like to hear your opinions <3