Maybe they don ' t look alike Wangnan wasn ' t wearing the ring at that moment . Taking into account how SIU remarked Karaka ' s good vision in his recent blogposts if Wangnan was actually wearing the ring at that moment , the plot hole would be bigger than the size of one of the tower ' s floor . Also Jinsung knows Karaka well , so he should have noticed Wangnan ring and his identity Hwa Ryun might have told him . So if he didn ' t notice that , it might be another plot hole , but he may know everything . If that ' s the case , why hasn ' t he said anything ? It ' s just because it ' s convenient for the plot ? Maybe Jinsung respects how Wangnan is able to live , making friends and trying to have a normal and joyful life despite the burden he holds on his back . I think Jinsung sees in Wangnan all the good that Karaka lacks , even having the same origin and purpose Wangnan tries to be a good person , that ' s why Jinsung keeps eating lollipops instead of smoking , because he respects Wangnan .