Forty-something beauty and mature woman, Yuriko Matsushima & Eriko Miura make their debut together! The eldest son of the Oshima family, Yoshiyuki, and his wife, Yuriko. The second son, Kei, and his wife, Eriko. These two couples have a tradition of returning to the husband's birthplace on the anniversary of the head of the Oshima family, Tosei. They light incense at Tosei's Buddhist altar and chat with the third son of the Oshima family, Mitsuo… This year was no different from usual, a typical summer scene for the Oshima family. However, Mitsuo was different. Mitsuo was plotting something... A plan to drive his two sisters-in-law into despair...
