Maina Miku, who has studied abroad and speaks fluent English, worked as a junior high school English teacher upon returning to Japan. She had a pure and well-mannered personality, but had long been aware of her own sexuality. Though taught at home that such desires were forbidden, her libido gradually intensified after entering the workforce, leading her to regularly masturbate while watching porn on her smartphone. Eventually, she developed a desire to experience the lewd, erotic sex she saw in videos—and decided to make her debut in the adult industry by actively pursuing AV stardom.