Trapped in thorny bushes

Everyone has a destiny, but why do some people seem happy while others suffer? Could it be that such people are cursed from birth and thus doomed to years of pain?
Occasionally, this suffering is so strong that only revenge can heal that person's heart.
Childhood was Chansung's worst nightmare. He lost his mother and several months-old sisters then. Bullied, challenged and despised by his classmates, he had support in his only friend, who was able to give her life for him. And although she came from the upper classes, she was clearly different from her siblings.
One day, Chansung disappeared without a trace, and that was the last time Chanmi saw him.
Ten years later, her sister, who was studying in America, returns home. To everyone's surprise, she brings with her fiancé, who in time the whole family is charmed by.
Only Chanmi gets the impression that there is something wrong with him. Will her fears come true and, will she manage to protect her sister, as well as the rest of the family, from the bloodthirsty Jungkook? Will she also protect her heart, which in time will begin to be open to him?