Fengxian

Fengxian was a high-ranking courtesan at Rokushoukan, a senior sister of the Three Princesses. Once a high-ranking courtesan of Rokushoukan, Fengxian was very beautiful in her prime; however, she had an arrogant disposition and wore a cold expression on her face. In her later years, she thinned and her skin became covered with rashes and gummas as a result of syphilis. She was an unsociable and haughty person. She was skilled at strategy-based board games. She was good at shogi but the best at Go.

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She is Maomao's biological mother.

(Source: The Apothecary Diaries Wiki, edited)