Yuko raised Taichi on her own, working hard every day while sincerely wishing for his bright future. Driven by her deep desire to spare him any hardship, she tirelessly supported their life. Eventually, Taichi graduated from university and secured a job offer in the printing industry. At last, Yuko felt she had fulfilled her duty as a mother, yet a growing sense of loneliness and emptiness lingered within her. She continued to live each day without meaning or purpose. Then, suddenly, Taichi invited her on a hot spring trip. Though confused, Yuko decided to accept his invitation.