Autumn, 1997. Ryuko, her brother Syuwa and their father Matsuo live in a small apartment. Matsuo loses his job after a quarrel and the Kato family's livelihood depends on young Ryuko, who secretly poses nude for various pornographic magazines. Matsuo ends up discovering his daughter's secret activity and throws her out of the house. Despite this, Ryuko continues working in the world of pornography and supporting her little brother and father.
