Sisters Ju-eun and Hye-jin lived a miserable life. After the death of their mother, their 'father', who had always been absent from their lives, suddenly appeared. Hye-jin, the older sister, agreed to his suggestion: if one of them joins the 'Daesung Group', he will rescue them from their poverty-stricken life. However... three years after entering 'Daesung Group', she dies in vain. This left Ju-eun struggling with despair at her helplessness in preventing her sister’s death. But then, she gets a new opportunity when she is brought back in time and Ju-eun decides to take her sister's place by becoming the daughter of the 'Daesung Group' that killed Hye-jin.

Sisters Ju-eun and Hyejin grew up in absolute poverty. After their mother’s death, Hyejin accepts the offer to join their estranged father’s wealthy family. But when Hyejin turns out dead just three years later, Ju-eun is grief-stricken. She grabs at the chance to travel back in time and take her sister’s place where she meets the kind but mysterious Iho.