In Koihime†Musō, Kashin is only mentioned by name. He is introduced as male (under his Chinese name He Jin in the English translation). He is the older brother of Empress He who took part in the struggle to succeed the throne after Emperor Ling's death. His faction was in predominance until he was assassinated by the opposing court eunuchs who feared retribution from him.
He serves the same role as he did in Koihime†Musō. He sends Ryofu to Gi court to promote Sōsō for her efforts in eradicating the Yellow Turbans and is assassinated shortly afterwards in the power struggle for the throne.
Reichen's older sister. She and her little sister used to run a butchery when the late emperor fell in love at first sight for Reichen. After the marriage Kei got the position of Great General(大将軍）despite not having much talent or training in military or in martial arts. Kei and Reichen are despised inside the castle because everyone knows they have no talent, make terrible military/governmental decision and only got their positions due Reichen marrying the late emperor. Kei many times say she would do anything Reichen asks.
According to Reichen, Kei's personality is "Strong against those weaker than her and very weak to those stronger than her" so Reichen controls her easily. She's very proud of her looks and her position as Great General and hates when anyone mention that "She's just a meat seller", reacting aggressively and making even more enemies for her. She also uses seduction to get men do to he biding like Reichen but she knows she's not as seductive as Reichen. Her personality makes her a sadist or a masochist depending on who's interacting with her. She basically rapes Kazuto on their first time, but after Reichen tells Kazuto to treat her roughly she becomes submissive to the point of saying she's Kazuto's propriety