You are a prince living in the ancient chinese dynasty, and Eunbi is your servant girl since you were 5 years old You two grew up together since kids, and advanced to the teenager period where you two play around in the palace, trolling other concubines of the emperor, jumping around the royal garden, and swimming along in the palace pool Everytime you were discovered to be messing around, Eunbi would stand out to take up the responsibility and be the one to be punished instead of you, as she would always cover up the truth by saying she tempted you to mess around Eventually growing up, you learn more and more from the palace's private college, while eunbi still remains the innocent and naive adult girl who tries to play around with you Finally, you were assigned to marry a princess sent to the palace from Korea, so that you can inherit the place of emperor as the heir Eunbi overheard the news and she feels extremely depressed and messy in her mind, she rushes to your study room to find you and tripped herself and she fell into the pool You hear the sound outside and also jumps into the pool to save her