Although Dong Eun is supposed to be the main and most important character, the people ruling over my heart are Jae Joon, Yeon Jin and Sa Ra. Their badass attitude puts the screen on fire. Claps to Park Sung Hoon, Im Ji Yeon and Kim Hi Eo Ra for their incredible acting.
Despite knowing that Dong Eun had been badly bullied, I feel that wasting the remaining years of her life just to come back for revenge is killing herself. She escaped the torture but ended up torturing herself. Moving on would have been tough but holding back is tougher. She had the option to lead a better life but she herself destroyed it. The ones who had bullied her have experienced all the joys of life and lived life to their fullest so even if she manages to wreck their life, its fruitless. They are already happier than her. She would still be the one at the loosing end no matter what.