The Taishou era continued for 25 years beyond the initial 15. A young woman, desperate to secure her family's future, prepares to marry a man whose name she doesn't know. However, her plans are derailed when her younger brother's death by self-immolation is discovered, with him holding an antique book at the scene. This incident leads to her involvement with the Imperial Library Intelligence Asset Management Bureau, also known as Fukurou, which claims that certain books known as Maremono have a profound impact on their readers.