A story of a married woman's heart and body trembling on a hot spring trip. She met her husband in college, married right after graduation, and has spent the past three years believing her role as a wife is to support her busy husband. But one day, she begins to question her life of simply obeying him, thinking, "I don't want to go on like this until the end." She chooses to embark on a journey with a stranger—her first and final betrayal. Depicted is a married woman being embraced by a man other than her husband, dripping with arousal, writhing passionately as her body is shaken to ecstasy. The warm yet intense night at the hot spring symbolizes the trembling uncertainty within her heart.