
I like the sunbae even if I don't like him being a 3rd party to the main couple. They're consenting adults and he made his boundaries clear from the start that he wasn't looking to date. But now that he is interested in someone, he actually went out if his way to properly break it off which shows he respects her even if it was just a fuck buddies situation. A real "insensitive playboy" would have just kept on fucking her whilst still in the middle of figuring out what he felt/wanted from Haneul.