Contract marriage with the heir to a large corporation. Through his late grandfather's will, Jihoo inherits the leadership of a multi-million dollar enterprise. However, the succession comes with a catch: he must take Eunyool as his bride and keep the marriage going for at least a year. Eunyool had walked away from Jihoo five years ago right before their engagement. Now she lives alone, raising her five-year-old son by herself. Jihoo needs his ex to secure leadership in the company. After coming to terms with the fact that no amount of effort can set her free from his grip, Eunyool accepts his proposal and their uncomfortable living arrangement begins. Jihoo has his wounds from their break up and Eunyool hold painful memories from the past she must keep to herself. Yet their heart flutters with each small movement and casual conversations from the other. As they peel back the layers of the past misunderstandings, the two comes face to face with a conspiracy they did not know existed.