Riko and her younger brother Akira vowed to support each other after losing their parents in an accident. Just then, their uncle Ginji approached them, eyeing the insurance money left for the siblings. Kind-hearted Riko couldn't resist and had her bankbook and seal stolen. Akira attempted to take revenge on Ginji but was instead overpowered. Threatened by this incident, Riko decided to offer herself to Ginji…
