Sofie Fatale is of mixed Japanese/French descent; in the film, she also serves as an interpreter, and is seen speaking English, Japanese and French fluently. She features most prominently in the film's House of Blue Leaves scene, wherein Beatrix Kiddo captures her and cuts off her left arm as a means of both seeking revenge on her for her presence at the massacre in El Paso and showing Ishii her intentions for a duel.

Kiddo later tortures her for the locations of the rest of the members of the Deadly Viper Assassination Squad, then sends her rolling down a hill to a hospital for medical attention so she can live on and tell Bill what has transpired, and that Kiddo is still alive. In the Japanese cut of the film, Sofie's willingness to diverge such concise information to the location of the surviving Deadly Vipers is attributed to the Bride removing her remaining arm in a crimson geyser of blood, with threats to remove her remaining limbs should she refuse the command.

It is safe to assume that while Sofie was not an official member of the DiVAS squad, she was at least involved in their operations and was in personal contact with Bill.