"I'm sorry... but I won't be able to come home tonight. I have to work overtime until morning." Behind these words lies a secret affair with department chief Kozuka that began a year ago. Due to the nature of her job, she often has to stay late into the night, leaving countless opportunities for them to be alone together at the office. Each time, Kozuka would whisper sweet nothings, eventually leading them into an illicit relationship. Currently, her husband is unemployed and struggling to get through each day. Witnessing his devoted efforts only tightens the guilt in her chest, yet she continues to be consumed by the forbidden pleasure. Caught between duty to her job and her family, her conflicted emotions spiral into one shocking development after another.