Yuto Okumura is in a happy marriage with his childhood friend, Sae, portrayed by Aimi Rika. However, Yuto faces a challenge as he is dealing with a erectile dysfunction that prevents him from fully satisfying his wife on his own.
When his wife finally found out that he has a threesome fetish with big breast girl, a concerned Sae decides to address the issue and support her husband. She approaches her friend Eimi, portrayed by Ohana Non, and proposes a solution involving Eimi's involvement to help improve their intimate life.
As Yuto anticipates the unfolding events, he can hardly contain his excitement, hoping that the newfound arrangement will strengthen their bond and bring happiness back into their marriage.