Aya Nakano is a married mother living in the same housing complex as her close-knit group of friends, with whom she plays mahjong daily. Despite worrying about her husband, she struggles to repay her mounting debts. One day, she receives a proposition from her mahjong buddy, Harayama, the neighborhood association chairman, to participate in a rigged mahjong game where another man will pay off her debts in exchange. This offer becomes a turning point that drastically alters Aya's life, plunging her into the depths of despair.