After losing her husband, Manami, a widow, lived each day in darkness. Though she had financial security and lacked nothing materially, a deep void remained in her heart. Her late husband's older brother and his wife, Kasumi, moved into a house nearby, and Manami's relationship with her brother-in-law gradually deepened. Sensing her loneliness, her brother-in-law began drawing closer to her, forging an intimate bond. Manami slowly became dependent on him, and their relationship evolved into something that filled the emptiness within her soul.