After losing her father, Yeonsu struggles to support her sick mother and little sister alone, and in desperation, she accepts a life-changing offer to be the surrogate for a handsome rich man named Taegun and his infertile wife. The contract seems simple at first, but Yeonsu soon realizes she's trapped in an arrangement she'll regret. As she questions her morality and self-worth, forbidden intimacy blurs the lines, and unexpected emotions begin to stir between Yeonsu and Taegun. But is anything real between them, or is it all just a complicated web of obligation and desire?