Fukuyama Rein has an eventful childhood: her mother died in a car accident when she was still a baby, raised by a Yakuza leader, then moved into the city of Tokyo to work as a car washer and construction worker to save up for her studies. All the time she thought she was already an orphan but one morning changed her life upside-down when men in black suits came in front her house and took her into a huge household. There, she met the owner of the household claiming to be her grandfather. Follow her in her transition from a simple lady into an heiress of a multibillion company. How can she manage school, studying about business, becoming a fine lady and having a love life all at the same time?