Hirata Nao, an ordinary sixteen-year-old girl in a single parent family, was happy leading an ordinary life with an ordinary dream to get married and make a warm home with the man she would fall in love with. However, her life is turned upside down when her father left her and her two younger siblings in debt of ¥10m (approx. US$100k) in search of a national treasure to repay it!With a huge debt to pay off, collectors at her door every other day, and two young siblings and herself to feed, she works part-time in three different jobs everyday, yet the return is close to nothing. But she doesn't give up hope.Per chance, or be it fate, Nao encounters Chikage Saga, an honour student of the advanced class from her school, who comes from an extremely wealthy background. Chikage offers her a part-time job with a pay so high that she would be able to pay off her debt in no time! Being at her wits end and considering the lucrative return of the job, Nao signs the contract without a second's hesitation. When she comes to and pays careful attention to the job contract... Contract? What contract?! It's a marriage registration! The romantic school story of a hard-working girl and her conquest marriage-of-convenience is about to begin!