Ayaka, a karate master with a strong sense of justice, stands up to a yakuza organization to protect her timid younger brother who is being bullied at school. Ayaka goes wild with karate, but her brother is taken hostage and restrained. Her sister is forced to masturbate next to her brother, who is tied up and raped, and is forced to commit incest with her brother's penis, which has been coated with an aphrodisiac! Ayaka's strong mentality collapses with a scream...