After a one-night stand with a stranger on the day she lost everything, Yunha loses her memory by accident and wakes up to find herself pregnant after two months. 6 years later, she reunites with her son Wooju's biological father, Hyunwoo, but his fiancée Seo-young tries to remove Yunha out of jealousy. Memory lost, relationships entangled, and truth hidden...Can the three be a family again?