Nana Mi Kawakami has been happily married to her coworker for nearly a year, enjoying a blissful newlywed life together. One day, Ono is transferred to her department as her new supervisor. Before her marriage, Nana Mi and Ono had shared a single intimate encounter. Since then, they've maintained a normal working relationship, avoiding any mention of the past while feeling mutual awkwardness. One day, a mistake in a document prepared by Nana Mi draws Ono's attention, forcing them to work overtime on a day off. Alone in the empty office, Ono makes a move on her. Feeling guilty over the error, Nana Mi doesn't resist strongly, and just like before their marriages, they cross the line again. This rekindled intimacy begins to stir new emotions, bringing unexpected changes to their relationship.