Jessica Jung's father left her family when she was only 8. He left when her mother was still pregnant with her baby sibling. Jessica's mom got drunk every night after her dad left, drowning herself in alcohol. Luckily, it wasn't enough to kill the baby, but her family struggled. Herself, her baby sister Krystal, and her mother. Jessica worked at a young age to help pay for her family. What happens when her mom dies when Jessica is only 17 and her baby sister, 7? Jessica's father takes them into his care, along with his family. It turns out Jessica's father left Jessica and her mother for another family, another family that has another kid, named Yuri. Kwon Yuri.