After her father's death, Lee Chae Rin seeks out revenge on the man who killed her father, who is no other than BTS JungKook's dad. A long the way she falls in love with JungKook himself and finds out shocking news.
JK wants to take revenge on Jimin's father, Park Jay, not knowing that Jay is already dead. He makes Jimin go through all of the torture  not wanting to believe Jimin when he's says that his father is dead. JK thinks that Jimin is saying that just to keep his father hidden.