Jinshi (壬氏, Renshi) is the deuteragonist of Kusuriya no Hitorigoto. He is a beautiful eunuch who was placed in charge of the inner palace and often requests for Maomao to solve mysteries in the palace in exchange for rare medicines. He finds Maomao's apathy towards him refreshing and amusing. Later, his childish curiosity evolves into a one-sided romantic affection.
Jinshi's most prominent feature his outstandingly beautiful face. Frequently described as having "the looks of a celestial maiden", he has an androgynous appearance, with long, silky black hair and pearl pink eyes. Unlike most other court officials in the series, he wears his hair in a half-back style tied with a cloth. While he wears an angelic smile on his face in public, he removes this persona in privacy and reverts back to the childish expressions he normally wears. He is most often seen wearing court official robes.
His appearance is said to be so captivating that a mere look at his face is enough to cause most girls and men to swoon; Maomao even fears that Jinshi could start a war with warlords vying for his affection. When Maomao puts lipstick on him, she comments to herself that he has reached a level of beauty such that, if anyone besides her, Suiren, and Gaoshun saw him, there would be a national crisis.
Despite his feminine face, Maomao comments that Jinshi's body is "surprisingly well-built", and that his hands are smooth and masculine, though callused from wielding a blade.
While Jinshi appears to be a serene and beautiful eunuch, he possesses a lack of self-confidence. Though he is intelligent and well-built, as noted by Maomao, he is neither a great scholar nor a brilliant general, and believes that he pales in comparison to the large shadow that is his brother, the Emperor. However, Jinshi is aware that his looks are extraordinary and thus uses his appearance and natural charm as a weapon in order to make up for his perceived mediocrity in other areas. Maomao notes that Jinshi has a double-sided personality in this regard; while he puts on an angelic persona in public, he is more childish and lazy than he lets on, a fact that only a select few know.
Influence: Being the brother of the Emperor, Jinshi has great political power and influence inside and outside the court--though, because he served as a eunuch rather than a royal for much of his life, it pales in comparison to his brother's influence.
Charm: Possessing a beautiful face that attracts both male and female, Jinshi is able to overpower most people and bend them to his will with his looks alone--though it can be a problem sometimes when his beauty attracts unwanted attention from eccentric people.
- In Chapter 28, Maomao comments that she finds it strange that Jinshi would use the character 華 for ka in his disguise name Jinka, since it means flower and has a feminine connotation. The significance of this character is later revealed: 華 is the last name of the Imperial Family, hinting at his true identity.