My name is Takeshi. I'm a college student, and I've been dating my girlfriend for almost a year now. Her name is Ryoka. She comes from a single-parent household—her mother, Keiko (49), raised her alone as a single mother. Keiko worked hard all these years to bring Ryoka up. But here's the thing: behind Ryoka's back, I've also started a physical relationship with her mother, Keiko.