Classmates Yuki and Sota, who attend a vocational school, are about to graduate without any romantic experience, still cherries. For their graduation project, they visit a hot spring inn deep in the mountains—a quiet, serene place they don't usually go to. There, they meet a woman named Sayako Sanada, who is traveling alone with a special purpose: hunting for virgin boys. Their encounter at the inn will become a turning point in their lives.