"Yuichi" who works at a major trading company and his subordinate "Aino" had an affair.The two, who are strongly attracted to each other, gradually deepen their relationship.However, "Yuichi", who has a family, always returned home on the same day after the affair, and the two had never spent the same night... It was their first trip to a hot spring... It was their first night together. .A man and a woman who have a passionate love affair at a hidden inn with the scent of Yunohana, far from their daily lives.