Go Eun-Nim is barely holding her life together, juggling poverty, a sick father, and dreams of becoming a teacher, when a wealthy family offers her a deal: become a surrogate and secure the money her family desperately needs. The transactional arrangement grows emotionally complex when she meets Baek Kang-Ho, the younger son of the family. Unacknowledged and unloved by his stepmother for being the child of an affair, Kang-Ho knows what it feels like to be an outsider. Yet in Eun-Nim, he finds something real in the unexpected spark of love. But love is never simple when secrets bind people tighter than blood. Eun-Nim believes her role in the Hoon family ends with the pregnancy, but as her connection with Kang-Ho deepens, so does the risk of the truth unraveling. Torn between duty and desire, sacrifice and longing, they risk everything for a chance at something genuine in a world built on lies.