In this chapter, we learn that people cannot be kind to one another, and that this is a disease that is incurable. We learn that it was not hanwoo's idea that they should fight, but that he did not want the two of them to fight over the key. Even if they could find the key, it would not be enough to make up for the disappointment in the locker. He says that he will lend the key to jooyeong so that he can go to the roof, but then someone will find him, and then he will not be able to help jinyeong, and so he will have to help him. .