Mitsuko Tachibana

Mitsuko Tachibana (橘 満子) runs the SM store that Kaoru frequently shops at. She has vast knowledge of SM and teaches Nana about various things involved in the life style. Often seen being sort of a mentor to both Nana and Kaoru.

Little is said about Tachibana in the main series of Nana to Kaoru; however, in the spin off "Arashi" more is revealed. She majored in Japanese history at Todai, studying culture and customs since the Meiji period. She even went to grad school. It is also hinted at in the main series, and confirmed in the spin off that her master is Kaoru's favorite author and role model, Sarashina.

Personality
Mitsuko seems to love S&M, and is a kind person, always willing to aid and help Nana, and Kaoru.