Miho is an enforcer for the Old Town Girls, however there is no indication that she is a prostitute herself.
Much of her past is unknown. She never speaks indicating that she may be mute.
The only man that has not met his end with Miho is Dwight McCarthy with whom she has an unspoken friendship ever since he saved her from Tong Gangsters several years before "A Dame to Kill For". Dwight is the only person that she has ever shown to have any kind of physical affection toward. Dwight often refers to her as "Deadly little Miho."
Miho's favorite weapons are her twin Katana Swords, she can use them with great speed and deadly accuracy.
When Dwight is shot multiple times in "A Dame to Kill For" he takes refuge in Old Town telling the girls about how he saved Miho from the Tong years earlier. This honor bounds the girls to help Dwight.
It is also during a raid on the estate of Ava Lord that Miho makes an enemy out of Manute when she crucifies him to a wall with her Katanas. Ever since then Manute has a strong hatred for the Girls of Old Town.
In "The Big Fat Kill" Miho kills Jack "Jackie Boy" Rafferty when he pulls a gun on Becky one of the Old Town Girls. Later when Dwight is attacked by Irish Mercenaries sent by Wallenquist to retrieve the body of Rafferty in a bid to take over Old Town, Miho saves Dwight after he sinks into one of the Tar Pits. She then plays a key role in setting up Manute and the other Wallenquist Enforcers for the final fight between Wallenquist and the Old Town Girls.
In "Family Values" Miho and Dwight get caught up in a war between Mafia Crime Families of Don Magliozzi and Boss Wallenquist after one of the Old Town Girls is assassinated. Again Miho plays a large role in getting revenge for the murdered prostitute.
Miho is tiny. Standing a mere 4' 10" and weighing less than 100 pounds, she is however very strong for her size and incredibly quick. She is highly skilled in the use of swords and other bladed weapons, as well as thrown weapons such as shuriken and she appears to practice some form of Martial Art. She is also highly skilled in the use of a bow and arrow. She seems to be totally cold and fearless and likes to play with her opponents especially those that use anti-Japanese racial slurs with whom she becomes extremely sadistic.
Frank Miller once referred to Miho as one of the "Supernatural Demons" of Sin City and that Miho is the good demon while Kevin is the evil one.
Miho was portrayed by Devon Aoki in the 2005 Film Adaptation.