"It seems that the light shines from noona . Even to you , is noona such a person?" Brother and sister, Ryu Bin and Ryu Seong, attract everyone 's attention wherever they go. However, Bin has a secret, and that is she has a crush on her classmate, Young-in. Younger brother Seong-eun, who has an inferiority complex to his older sister Bin, begins to approach Young-in, a shy and quiet girl. Three children who are becoming adults and their rather noisy growth story .