According to her official profile, Hitomi Kobayashi was born in Tokyo on September 2, 1965. However, in an interview in the just before her retirement in 2003, she confessed to have actually been born in 1963. Her ambition since childhood was to be an actress. She attended acting school, and registered with a talent agency. Kobayashi was not particularly sexually precocious, claiming at the time of her AV debut, "I lost my virginity at 18, which is probably a bit late, and I wasn't very experienced with men."