Is it love? Is it friendship? Or is it sisterly love? It doesn't matter what the relationship is, what matters is the special feeling between each other. A special feeling is destined to make you different from others. Parallel lines may never intersect, but they will always be together.
Concept: What kind of sparks will come out of the collision between Lin Xi and Su Lan? The ignorant emotions in adolescence are like two parallel lines that cannot intersect.