A loyal and overprotective bodyguard of Sonken who almost never leaves her lord's side. She feels thankful towards Kazuto as he has made Sonken happier and more lighthearted, which she wasn't capable of.
She's one of the very few that actually thinks highly of Kazuto's kindness rather than criticizing it as a weakness. Unlike other girls, she wears a female version of fundoshi.
While normally calm, she becomes hotheaded when someone questions her loyalty.
In the third season, she served as Ryomō's commanding officer, assigning her to be Sonken's bodyguard. She was furious when Ryomo almost failed to protect Sonken when a thief snuck into the palace storeroom and Sonken was the one who subdued the thief. Even though Ryomo redeemed herself by preventing an assassination attempt against Sonsaku, Kannei discharged her from her troop by telling her to relinquish her fundoshi, the symbol of her troop. However, it was revealed that Kannei requested Shūyu to take Ryomo in as an apprentice strategist to Sonken, feeling that Ryomo is more suited as a strategist rather than a bodyguard.