My girlfriend has a younger sister who attends an all-girls school. One day, when I went to her house to play, her sister clung to me while whispering obscene words in my ear, bringing my dick to the brink of orgasm. Taking advantage of when her sister was asleep or taking a bath, I forcibly had sex with her sister and came inside her. Although I felt guilty, her sister was too much of a little devil for me to resist…
