Set against the backdrop of the bustling Yeongpo branch of KCU Bank, "The Interest of Love" is a realistic romance drama that explores the complicated and nuanced nature of modern relationships. The story follows four individuals—Ha Sang-soo, Ahn Su-young, Park Mi-gyeong, and Jeong Jong-hyeon—who all work at the same bank but hold vastly different views on love, security, and class. As personal ambitions clash with romantic desires, they find themselves entangled in a web of unspoken feelings, jealousy, and hesitation, realizing that love, much like finance, comes with risks, interest rates, and painful investments.