Born in 1962 in Tokyo, Seino entered the Chuokoronsha publishing company in 1987 where she worked as an editor at Marie Claire magazine. She began taking pictures in the 1990s, and after leaving Chuokoronsha in 1995, devoted herself to photography. Her most notable photo books are The Sign of Life (Osiris, 2002), which focuses on unpopulated landscapes in Chiba, Ibaraki, and other parts of Japan, and the posthumous work Everywhere – Gather Yourself – Stand (Osiris, 2009), in which she broadens her focus to capture towns and people, primarily in Tokyo. She died in 2009.