On the first page, Jun receives the "Will you wind? Will you not wind?" letter, and decides not to wind.
Skip ahead to a different time and place. A loser junior high school dropout named Shimada is struggling to put himself through college. He is troubled by vague feelings that he is not in the right place, that something is missing from his life. Then he starts receiving mysterious packages containing doll parts and manuals titled "How To Build a Girl". The manuals contain instructions on building a doll labeled "Shinku". Shimada feels strangely compelled to start building her.
At the end he receives a text message from Jun Sakurada, demanding his help, saying that he and Kanaria by themselves can't fight against the strength of Kirakishou or escape. "Shimada" looks at the name and thinks, "A mail from the past *me*...?"