Sayaka's family is rich, but her parents suddenly go missing. She took a part-time job in a family restaurant. But Kuroki, the boss of the restaurant, says that her family disappeared due to large debts and to pay off the debt of her parents, Kuroki gives her an idea: "Our restaurant only offers special services at midnight. Putting your name on the menu will help you pay off the debt faster." ... Sayaki decides to work at night to pay off her parents' debts.