Sumire raised Kouta single-handedly with all her might. Thanks to her efforts, Kouta graduated from university and secured a job. As Kouta began living on his own, Sumire reflected on her life. She was happy that Kouta had grown up so well, but what about her own life? One day, Kouta invited her on a hot spring trip. The hot spring trip of Sumire, who was troubled by her own life, and Kouta, who didn't care about his father at all and was optimistic, began.
