Jimin and Nayeon are engaged. Just right before they were going to get married, Nayeon was involved in a hit and run incident. Before Nayeon die, her last words to Jimin was, "Remember our promise. Promise to find my little sister Jimin."
Meanwhile in United States, Kim Karina is adopted into Kim Yeri's family, but is treated like crap. Although Yeri and her grandmother mistreat Karina, Karina still love them both. Just when things were going to get worst for Karina, everything change when she meet an old man, Park Jung-Won who is offering to change her life forever.
Min Yoongi is getting married with Park Jaemin, and he has to meet his family, but at the moment he saw his fiance's brother, Park Jimin, he knew he was fucked.
*based on @Yonniemoon 's Twitter au