Kim Hye Yoon Rowoon Li Na'en Lee Jae Wook Kim Young Dae
Dan Oh, a wealthy girl with congenital heart disease, one day she suddenly realizes that she is a character in a comic. Then she begins an adventure to find her true life and love. In the process, she comes across Haru, a male high school student whose student number is "13". Gradually, they develop a heart-wrenching romantic story.