At night I wanted to jerk off really bad because I saw my step-sister in her underwear. While no one was looking, I went into the bathroom and began to slowly masturbate my penis. Imagining how I was fucking my step-sister, I began to jerk off more intensely. Then I let go of my dick and waited for the sperm to shoot out of my hard dick on its own. This shot was very powerful. I felt a strong orgasm from such a hands-free cumshot