Murase Masasuke holds the position of Chief Scribe, maintaining historical records within Edo Castle during Shogun Yoshimune's reign. At 97 years old, his birth coincided with the early spread of the devastating Redface Pox pandemic that drastically reduced Japan's male population. This advanced age makes him one of the few surviving witnesses to the societal transformation before and after the pandemic. He is the son of the influential political figure Lady Kasuga. She orchestrated the initial gender-role reversal within the shogunate following the death of the male Tokugawa Iemitsu. On her deathbed, Lady Kasuga appointed Masasuke as Chief Scribe. She tasked him with documenting the pandemic's impact and the subsequent societal changes in a record titled the *Chronicle of the Dying Day*, fearing the plague could lead to Japan's collapse. She instructed him to continue chronicling events until the very end. Masasuke dutifully preserves and updates the *Chronicle* across decades, compiling detailed accounts of pivotal events. These include the rise of the first female Shogun (Iemitsu, originally named Chie), the establishment of traditions like women adopting male names in official records, and the creation of practices such as the "Secret Swain" ritual involving the execution of a Shogun's first consort. The *Chronicle* serves as the shogunate's institutional memory. During Yoshimune's reforms, Masasuke provides crucial historical context when consulted about administrative inconsistencies, such as the tradition of women assuming male names upon inheriting family leadership roles. He reveals to Yoshimune that his mother, Kasuga, was a woman and clarifies that the original Shogun Iemitsu was male—facts obscured by decades of rewritten history. He presents Yoshimune with the *Chronicle of the Dying Day*, enabling her to understand the origins of these customs and the traumatic circumstances surrounding the female Iemitsu's reign, including her institutionalization of the Secret Swain ritual following her own rape. Masasuke remains in his role as Chief Scribe until at least Yoshimune's time, maintaining the *Chronicle* as a continuous historical archive. His lifelong dedication to this duty underscores his function as the living link between the shogunate's past and its present.