Takami Jin's Links
Jin didn't acknowledge Christopher's presence the first time they met, he would just shrug him off, but as time moves on, he gave in to Christopher and thought this guy won't give up, but then they became much closer.
Impressed by him and his lifestyle, Christopher started following Jin around, trying to gain his attention. Eventually he succeeded, when Jin finally gave in.
Jin loves his sister, he would protect her with all his life, even though he clearly knows, Mikan can handle herself.
Jin is her big brother, he may have been disowned by their parents, but Mikan still loves his big brother