This drama is based on the web novel “Moonlight Drawn By Clouds” by Yoon Yi Soo and illustrated by kk which was originally published online from 2013-Oct-03 to 2014-Oct-10 on naver.com. Hong Ra On (Kim Yoo Jung), disguises herself as a man and counsels men on dating. Due to a love letter she wrote for a client, she meets Lee Yeong—future Crown Prince Hyomyeong (Park Bo Gum). Hong Ra On is unaware that he is the Crown Prince and Lee Yeong is unaware that Hong Ra On is a woman. The Crown Prince becomes interested in Hong Ra On. His eunuchs become aware of this and attempt to get Hong Ra On to become one of them