I will tell you everything!” The marriage of a newlywed couple and a cousin’s sister begins strangely! Yoon finds out that the new vice president for the company is Hyunju, the nephew of his new father. Finally, Hyunju, who was looking for a house, asked Yoon to ask her to live for a while, and Yoon Jae can not refuse Hyunju, a boss and cousin sister. It is the strange coexistence of the cousin sister mixed with the Yoon Jae family that started so. However, my cousin’s sister starts to interfere with the sex life of the couple.