"Will you marry me?" A 2 billion won proposal to a mercenary from a private military company. The condition: a marriage lasting one year. "Are you crazy, ma'am?" "I need a crazy person who wouldn't mind having a divorce on their record, and you're the only one." Lee Rae-hwa, the only daughter of Daesan E&C. To escape her stepfather's control and complete her paintings, Rae-hwa hires a legal guardian for one year to protect her. However, Gwon I-tae, the only hope she employed, turns out to be a wildly unpredictable and crazy person. What started as a contractual marriage and cohabitation begins to drift in an increasingly unusual direction...