A couple who are childhood friends, Rei and Philosophy. Five years into her marriage, she has remained as friendly as ever, but this summer, it is discovered that she is having an affair with Philosophy. Trying to get a baby with her didn't go well either, and Rei fell into the depths of despair. At that time, Dango, her philosophy father, comes to stay at her house while on a business trip to Tokyo. She reunites with Dango, who has been nice to her since she lived in her hometown, and Rei becomes attracted to him. When Rei realizes that she has been subtly seducing Dango, she makes up her mind and heads to Dango's house...