Daughter of a Chinese woman, who spent her childhood in Nishi Ku (Fukuoka City). When she was in elementary school, her parents divorced and she went to live with her mother, who ran a little restaurant. Being a child she practiced karate in junior high school, represented Kyushu in several competitions and finally won the woman national karate championship. During her attendance in the Nippon College of Health and Physical Education for women, where she studied physical education, she saw the film "Young Master" (1980), directed and starring Sing Lung, and decided enrolling JAC (Japan Action Club) to become a stuntwoman. She finally changed her name to "Oshima" and debuted in the TV series "Super Electron Bio-Man" in 1984. At that time one part of JAC, "Asia Action", became independent and based in Hong Kong and Yukari decided to leave Japan. Chinese director Hung Kam-Bo gave her a bit part in the martial arts film "Shanghai Express" in 1986 and thus she began a career in Hong Kong until 1994, when after more than 20 Chinese films and a divorce from star Cheng Ho-Nam she established herself in the Philippines and changed her name for the second time to "Cynthia Luster" (Sincere Raster). Here she would participate in more than 20 films.