Go Eun Nim is in a desperate situation. Struggling to support her poor family and sick father while studying to become a teacher, she's running out of options. Baek Sae Hoon is the oldest son of the Hoon family and stands to receive all the family inheritance, but he and his wife cannot conceive a child. Resorting to surrogacy, the couple goes to Eun Nim with a proposal she cannot afford to refuse. Sae Hoon's younger brother Baek Kang Ho, meanwhile, is the bastard child of an affair their father had, and his stepmother despises him as a result. Eun Nim thinks that carrying their baby will be where her connection to the Hoon family ends, but unexpectedly she and Kang Ho begin to fall in love.