MacySan
I just want to clear this thing out, I already stated that how Sungji and Dawoon feel toward each other doesn't necessarily mean they will end up together, at least not now. If anything, it added a new perspective to Sungji's.
Dawoon was a girl that was more of a filler of a character rather than an important one
if you think this is true, let me point out that Sungji was always thinking about Dawoon, and Dawoon has from the beginning left an effect on Sungji, in a matter of fact, Sumin resembled Dawoon in Sungji's mind at some extent.. you may not agree with me about this intuition but it's clearly made and shown in ch62 (notice this very clear comparison that she made), this is regardless of the fact that Dawoon and Sumin are indeed different. Dawoon didn't need to appear much, but her words and her memories in Sungji's mind from the very beginning are what mattered and what made us reach her current resolve.
Having developed Sungji and Sumin so much, only for Sungji to go back to an insignificant character would be really weird.
Sungji never been an insignificant character, by the way, Sumin and Sungji dated for 4 months and a week.. look at the effect she made in the whole story.
I've been reading this Manhwa in depth now, I never felt that there was any filler in it. In fact, the story itself is bigger than what we get now... bigger than the love triangle.. look at Baeks for example, they deserve a whole Manhwa.. do you really think they needed a filler ?