Ryuko was raised by her father, a gambler named Senzo Yano in Kumamoto, Kyushu, after her mother died when she was little. When she turned 18 years old, her father was attacked and killed by a stranger in alley. Ryuko then dissolves her yakuza family, and, carrying the wallet left by the killer, she sets out on a journey to avenge her father's death.
Five years later, she wanders the nation, known