A beautiful woman is skinny, cheerful, and possesses long hair and an elegant facial structure—and she is not Kang Mirae. Since she was young, Mirae has always been the ugly one, being rejected nine times and considered undeserving of love. Fed up, Mirae becomes a "Gangnam beauty," someone who undergoes numerous plastic surgery procedures to make themselves beautiful.

However, as Mirae enters university to pursue her dream of becoming a perfumist, things don't exactly go according to plan. People constantly ridicule her as a "plastic monster," an easy and artificial woman. This is in full contrast with Hyun Sooah, the belle of the school whose appearance is completely natural. As Mirae struggles with her self-esteem and what it truly means to be "beautiful," she comes into contact with Do Kyungseok, a former middle school classmate who questions her fixation on appearances.