
I actually thought for a second that In Suh was shocked to see how bad Yool's injury was once he saw it, but no. He was just upset that it "almost reached his hand." He doesn't care about Yool, he just cares about his piano playing abilities

you know, that was the only scene that showed that he, in fact, worry about him. because the piano is important for yool. because it is his dream. and insuh knows he took it from him and he knows they will eventually break up, there's no salvation for their relationship. so if yool lost the piano he would be left without nothing.
"I can kick your ass too, pretty boy"
"You can try, princess"
This is the type of petty bickering flirtation that I LIVE FOR
Yes yesss isaid the same thing