Des:Yuzuki, a virgin, has been studying through videos and books in order to have a girlfriend for the first time and have sex for the first time. Then, J●s younger sister came and asked, Do you want to practice with me?...! ? She is forced to teach him how to kiss, but the lecture quickly escalates. She loses her reason due to the completely grown-up body of her younger sister, and without hesitation, she starts sucking on her raw pussy, which develops into forbidden brother-sister sex...!