The Taishou period overstayed its initially planned duration by an additional 25 years. In order to support her struggling family, a young woman agrees to wed a stranger, only to have her plans change when her younger brother dies mysteriously while holding an ancient book. Following her brother's demise, the "Fukurou" agency, also referred to as the "Imperial Library Intelligence Asset Management Bureau," pays her a visit and informs her about the existence of powerful tomes called "Maremono," which have a significant impact on their readers. Since the girl is now able to see what are called "Auras," which are the emotions emanating from the Maremono that were formerly invisible to the human eye, it appears that fate has intervened. Despite her reservations, the girl resolves to escape her sheltered existence and enters the imperial capital, where she encounters treachery and darkness. Will she be able to overcome the obstacles and uncover the truth, or will she fall prey to the shadows? Emotions such as envy, animosity, derision, empathy, and affection await her.