Yui, a married woman entering her 15th year of marriage. She had long suspected her husband of infidelity. One day, she finds concrete evidence of his affair. When confronted, her husband admits to it. From then on, his attitude towards her becomes increasingly harsh. Their daughter, unable to sleep, clings to her mother. Their family slowly begins to crumble... Desperate to make her husband understand the pain of being cheated on, Yui meets a man she connected with on a dating app and invites him home to have sex in front of her husband.