im sorry if im so bad at explaining but this is from my understanding
from hyungseo : "i will desire you even if you dont love me" which could mean a misguided obssession he have for jiwook
from seungeon : he knows the he and jiwook have different sizes(or point of view?) of love, but he will still love jiwook regardless "even if he doesnt love me" one day
from jiwook : he takes the "even if you dont love me" literally, in a sense that it doesnt hold true, i could be wrong but maybe jiwook didnt really believe that seungeon could still love him after all those years.
sorry if its not understandable i suggest u guys wait for the authors note when it finishes for more accurate description
Now that i think about it, "Even if you dont love me" seems more likely to be Kwon Hyeong Seo's words.