Ishino Shinsuke is a businessman living in Tokyo with his wife Anna and son Taichi.
The couple is worried about having a second child.
Taichi was conceived through fertility treatment， as both men had difficulty conceiving.
The pain of having a second child means that they only need to have sex， but just when they thought this would be enough， Shinsuke develops erectile dysfunction.
To improve his erectile dysfunction， he confesses his cuckold fetish and suggests to his wife Anna that he let her cuckold him.
His wife Anna， who desperately wants a daughter， reluctantly agrees.
As he cuckolds her more and more， his erectile dysfunction improves， but at the same time， his wife Anna starts to change…
