Seibu Department Stores, Ltd. is promoting a 38-year-old division manager to head of its popular Yurakucho branch -- and she's a woman.Yoshino Tominaga, chief of sales training at the firm's head office, will be the first-ever woman head of a department store in Japan, according to the firm. She will also be the youngest-ever branch head at the firm, male or female.Tominaga was promoted for her management skills and expertise in selling women's clothing, the firm said. It also said that it will increase the number of female bureau chiefs in the company from 10 to 20.