Haruka is the wife of Yakuza boss Oni Juuma. She is the mother of three children: Hirohito, Kenji and the youngest, Katsuko. She also appears to have another son named Naoki, most likely from another father. When she was pregnant with Katsuko, she attempted to leave Oni, claiming the she only married him because she had no choice. Oni told his men to find her and bring only his daughter back, making it clear that he wanted her dead (Green Hornet: Blood Ties #1). 
 
After the defeat of Oni and Hirohito (the Black Hornet), she resurfaced as the leader of the Juuma Clan. This has yet to be explained.