Tanaka Ichirou spent much of his early life being transferred from school to school, and those constant moves left something behind: twelve relationships with twelve different girls across twelve different cities, each one ending not with a conversation but with a new address. Now, near the start of his third year of high school, a letter arrives containing only four words: "I want to meet you." The sender is not identified. Finding her requires visiting each of the twelve cities in turn, reconnecting with everyone left behind, and hoping that when the right person appears, he recognizes her.