Nagasawa Azusa married her former college professor and, to assist him with his thesis writing, allowed her senior colleague Oki to frequently visit their home. However, Oki had developed deep romantic feelings for Azusa, struggling to conceal his desire. One day, a friend warned her to be cautious around Oki, but before she realized it, Azusa became entangled in his emotions. Amidst her ordinary life with her husband, new feelings began to stir, intensifying the conflict between love and family loyalty.