hii uhmm for me i think sangwoo doesn't really have feelings for yoonbum. yes they been together all the time but sangwoo was just using yoonbum til the end. for me, the reason why sangwoo's last word was yoonbum's name was because he thinks it's bum's fault that's why he's in the hospital,,,, like their typical antics yoonbum did something, sangwoo gets mad to yoonbum etc. that.
that's is my opinion on your question and i do respect what you believe because i, too, wants to believe sangwoo do have feelings for yoonbum ╥﹏╥ but 70/30 of me knows he doesn't

I really want to know if Sangwoo really loved bum. The author said that we probably would know the answer based on the last chapter however I have mix feelings about it. What do you guys think? did he or did he not? I want to believe he did based on the last few scenes. ╮( ̄▽ ̄)╭