I was so mesmerized by her defenseless ass that I wanted to fuck her without even looking at her face. So I immediately entered her and vigorously pistoned, ejaculating inside her vagina as if it was just a hole for sexual relief. Whew, I thought it felt good, but then I realized the hole I thought was her was actually her sister, and it was a big mess! I should have been at a dead end, but she said, "Since it's a secret from my sister, let's do it more..."
