jung jae-hyun, the only son or heir of the Jung family who owns a Seoul pharmaceutical company under his auspices and owns the largest bio lab/bio pharmacy in Seoul. jae-hyun just finished his second bachelor's degree at Oxford University majoring in science at the age of 29, now he has returned to Korea.

his family lives in the most luxurious and expensive mansion in Seoul, has a garage with a collection of sports cars, a private circuit, a golf course in the backyard, a basketball court, a private jet and many more. His family also has many shares in several large companies in Korea, such as Samsung and a baseball club.

jae-hyun is not close to his parents, this is because since he was little he was cared for by nannies because his parents were busy with their careers. since his teens, jae-hyun has often participated in international science and mathematics olympiads and won many awards. jae-hyun does all this to make his parents proud, but they are never satisfied with everything jae-hyun does.