Mone Endo's family runs a long-established hot spring inn, with her father as the owner. However, due to sudden financial troubles, the business collapsed, and both her parents disappeared without a trace. Working as a dental assistant in Tokyo, Mone is unable to return home and lives each day with growing anxiety. One day after work, as she returns to her apartment, debt collectors suddenly show up at her door. They demand repayment for her father's massive debts, and with her parents nowhere to be found, the burden falls entirely on her. Threatened that her apartment floor will be seized if she fails to pay, she reluctantly chooses the path of fuzoku work, marking a dramatic turning point in her life.