In spring, 2006, Shin Sol-I (So Ju-Yeon) is a 17-year-old high school student. She has loved Cha Heon (Kim Yo-Han) for a long time. Cha Heon is her classmate and also a childhood friend. They happen to live next door to each other. Shin Sol-I tries to express her feelings to him, but it doesn’t go well.