The two siblings, who have developed an inappropriate attraction to their elder brother-in-law, Yufuyu, find themselves appealing to him even when they are asleep or awake. Adolescent Yufuyu is unable to take a step forward due to the sisters' impatient advances. However, there seems to be no way for him to resist Ayaka and Haruka's persistent appeal...? Forbidden first sexual encounter with two older siblings! The battle between the sisters over their younger brother's genitals never ceases...!