Rieko has raised her son Shuichi single-handedly. However, perhaps because she was too spoiled, she acted selfishly and secretly bullied her classmate Hajime. When Rieko finds out about this, she goes to apologize to Shuichi on her behalf, but... Hajime, furious at her convenient offer, asks her to serve as an apology using her body. Furthermore, she pushes Shuichi, who knows nothing about her, to exact her revenge.