Cha Eun Sung could be a much better character if she were less weak. Always being pushed around, not defending herself or her wishes. The way the girl sees herself... not worthy or good enough... that's such a prejudiced view of the world and, worse still, of her own circumstances. Writers, it'd be great if you didn't build an interesting character just for us see her lose all potential by making her "pitiful", by taking her volition, her voice.
She just stands there, dragged by Yeong Do, by Kim Tan. Speak woman, act on your wishes and goals.
SEE how strong you are/can be!