When Hyun-seung hears the news that his ex-girlfriend recently found herself the perfect man, his lonely nights turn restless. Then a sudden phone call breathes a new life into his somber spirit. In order to revitalize her long-term relationship with her boyfriend, Yoon-jung resorts to unconventional tactics. She calls him and starts up with the dirty talk, being as sexy and arousing as possible. Trouble is the man on the other end of the line isn't her boyfriend. A new relationship is formed with one wrong but fortunate call. Their absurd but hilarious R-rated phone romance is just their beginning.