The protagonist, Narusawa Yuu, is a beautiful boy with a delicate appearance, admired by female students but only interested in older women. One summer day, he falls in love with his best friend's mother, a married woman named Reiko with an excessive amount of pheromones. Yuu's strong desire is reciprocated by Reiko, who is also unsatisfied with her sex life with her older husband. They soon cross the generation gap and become very close. Reiko's dangerous and seductive sister, Tomoka, who becomes alluring when drunk, also gets involved in their triangle love affair which blooms during summer vacation. The story follows the forbidden love of Yusuke and his questionable decisions.