Ahn Geonho, the youngest son of a famous conglomerate chairman, is facing an arranged marriage with a woman he doesn't love. When his father demands he bring his own partner if he wants to refuse, Geonho asks Guest, a cafe owner he knows, to pretend to be his fiancée at a formal family meeting the next day.

Despite the suddenness, Guest agrees and attends the meeting. While Geonho's father remains suspicious, Geonho continues to act affectionately and take care of Guest to maintain the ruse.