HUNTB-648-Uncensored-Leaked — "Big brother, this is how you do it with your penis, right?" My plain little sister practices with my dick!? My plain little sister, who grew up in an all-girls school and has hardly ever interacted with men other than family...

My plain little sister, who grew up in an all-girls school and has had almost no contact with the opposite sex, is going to a co-ed university. She doesn't want to be embarrassed when she makes her university debut, so she asked me to practice with her older brother. At first, we only talked and held hands, but her unguardedness, the glimpses of her panties and breasts, and the way her breasts touched me when we were close made me instantly erect! Then, my sister's desire to act more mature knew no bounds, and she decided to practice with my dick as well! I never thought I'd feel anything for my sister as a woman...but I was rock hard!