I was grounded by my girlfriend, and I had an insatiable sex drive. So, I often didn't even look at the face of whoever it was, and just thrust my erect penis into the exposed buttocks without any protection, pounding away, and ended up ejaculating inside the vagina. Ahh, it felt so good, but then I realized I had inserted it into her sister's vagina, and now I'm absolutely doomed! Or so I thought, but it was like I had lit a fire…
