Mariko is divorced from her husband and lives with her eldest son, Naoya, and her second son, Daisuke. Maybe it's because of the loneliness of not having a father ... Naoya and Daisuke had little feeling of "sharing" and were always playing brothers. Mariko was educating her brothers to "share", but in reality she had a physical relationship only with Naoya. However, one day Daisuke learns the fact. And Mariko decides to "share" another hole, "anal", with Daisuke ...
