Seo Joon-Hyung (Lee Jin-Wook) works for a large company. He is 30-years-old and single. His life goes smoothly, being happy and financially secure. His girlfriend is Kim Na-Eun (Lee Yeon-Hee). She is in her 30's. They have been in a romantic relationship for two years and they are about to marry. Kim Na-Eun is affectionate, bright, smart and a realist. She also works for a large company. While Seo Joon-Hyung and Kim Na-Eun prepare for their wedding and life as a married couple, they face many problems.