Based on the erotic game by Orcsoft.

Sanae is the wife that anyone would be jealous of. She is young, very sexy and gentle.

However, after 4 years of marriage, her husband worries if is he good enough for his wife. For a long time he is not able to have a sex with Sanae, but she never complained about it. He starts to think of way to make his dear wife happy and finally asks for his friend to have a sex with his wife. While he's secretly watching his wife with other man, he starts to feel incredibly stimulated...