In the last year on her high school, Song Jieun becomes so possessive noona for his 'brother', Jung Daehyun. There is a reason behind it. Jieun who used to be an innocent girl turns to be cold in front of Daehyun's friends who steal Daehyun's times. And then, there is a new boy in Daehyun's class who always teasing her by being Daehyun's best friend. Later, when Daehyun has a girlfriend, Jieun realizes that her beloved 'brother' is the one who stays away from her.

"This one year only, please be with me, only me."

- Song Jieun