I was chilling at my friend's house, we drank a bit and he felt asleep pretty quickly, so me and his female sibling moved him to his room. After that I stayed in the living room talking to the female sinling, the thing is when I drink I get super horny. So I was basically desperate to jerk off, and I jokingly told her I needed to go to the bathroom to rub one out, and she said it was okay, I could do it right there. I laughed and told her I seriously needed to go, and she just started rubbing my croch, feeling my rock hard dick underneath. Then she pulled it out and started stroking it like a pro, and liking the tip until she drank my cum until I couldn't bust anymore. I said thanks and offered to pay her back the favor, but she said she had a bf and went upstairs. I just stayed in the living room thinking how hard I'll fuck her next time I'll see her.