Reina Otsuka, a 38-year-old single woman, had long dreamed of marrying her longtime lover from her school days, but their relationship ultimately fell apart. Since then, love never came her way, and after turning thirty, she threw herself entirely into her work. As her friends around her one by one got married, had children, and appeared happily settled, she began to feel a deep sense of loneliness, as if left behind. Seeking to soothe her emotional and physical longing, she plans a private hot spring trip. On this journey, she meets someone who awakens her passion, and they surrender to intense desire, drowning in pleasure. Thinking, "I want to be loved deeply today," she loses all restraint, her mature body trembling and writhing as she climbs toward ecstasy. In stark contrast to her daily grind, the fleeting sense of liberation during this trip fills her heart with fulfillment.