Maomao, the protagonist of The Apothecary Diaries , is 17 years old at the start of the series. She is depicted as a highly skilled and mature apothecary despite her young age, having been trained from an early age and working independently by the time the story begins

. As the story progresses in the light novel, Maomao ages; by volume 8 or 9, she is around 19 or 20 years old, reflecting the passage of time within the narrative

. In the anime adaptation, which follows the early part of the story, she remains 17 years old

. Therefore, at the beginning of the series and in the current anime episodes, Maomao is 17 years old.