From a review by Chris Mayo found here:
Seppuku was a code followed by samurai warriors to avoid the shame of falling into enemy hands. The Daimyo (or feudal lords) could also order samurai to commit seppuku. Dishonorable samurai were sometimes allowed to choose seppuku rather than face a disgraceful death by a normal manner of execution. The purpose of the act of seppuku was designed to protect and restore the honor of the samurai warrior.
Seppuku lives on today throughout Japanese cinema, from sick fetish films to Yakuza crime. While the films predominantly do not showcase the ritual suicide of samurai, as it stands, Seppuku is shown as more of a fetishism within modern Japanese culture. A prime example of this can be found in Fuji Kikakuâ€™s presentation of Ah-01: Onna Harakiri: Sange, produced by Right Brain.
Rb-01: Onna Harakiri: Sange begins with a woman sitting in a dark corner, lighted by nothing other than a small lamp. She stares at a soldierâ€™s uniform in mourning. We fade to white. Thus begins our journey into the cinematic form of ritual suicide.
Crawling at a snails pace, the film continues with the woman sitting on a white sheet, now appearing in a pinkish colored outfit. In front of her sits a knife in its sheath. After caressing if for some time she finally begins to remove it from its case. Taunting the viewer, she decides to place the knife back in its sheath, leaving you wondering when she will even follow through with the inevitable deed…