yuri seems like he has BPD (Borderline Personality Disorder) and seonwoo would be his FP(favorite person). between his mood swings, obsessive/possessive behavior, the very obvious abandonment issues-- among other things-- and along with the fact that he wasn't loved properly as a child and was neglected and abused, it makes sense. i have bpd and he definitely, in my opinion, has a lot of symptoms that fit the diagnostic criteria. i already thought he needed therapy, but especially after i made this realization.
someone please animate this.. turn this into an anime. i'm begging. i'm gonna be reading this for the rest of my life bro, and i'd watch the anime all the fuc**** time.