I slept with my sister's husband over the holidays. A little too much wine and he said he went to the wrong room when we spoke the next day. I knew what was happening but I didn't stop it. I am sure he knew too because he would later leave me to join my sister for the night. My sister is heavier, much larger breasts and has had two children, he had to have noticed the difference before and during but again, I let it happen. He was a great lover or good at sex for sure. Of all places, I slept with him in my parents bed in the room next to where my sister was sleeping. OMG, my whole family was in the house. My parents just gave me their room so I could be closer to my sister and her children during the holidays. I thought I should stop him when he first came stumbling in the room but I didn't. He stripped down naked and snuggled. I felt his large penis against me. He kissed and touched my body. He caresed my breasts and fingered my womanhood. I had too much to drink too but I let it go on knowing it was wrong. After a while I was so horny I let it go to the point of no return. He touched my sensitive nipples and caressed my breasts with his hands and mouth. I am not that experienced and he is very endowed (so I found out). I am at a quandary as what to call what we did. Did he screw me, did we fuck or did we make love. What ever it was, I wrapped my arms and legs around him and held him tight as he buried his penis in me with varying pace and depth. He lasted much longer than any man (only two others) that I had slept with until then. It wasn't until he changed pace and moaned in my ear that he was going to cum as he neared orgasmed that I woke-up out of my state passion and lust and realized that what i was doing was stupid. Oops, too late. I am not dating or seeing anyone so why would I need protection but how would he know that? A louder moan, was that mine or his? OMG it was me, I was orgasming as my brother-in-law fucked me. A few hard thrusts that rocked the bed and shook the room. The feel of his penis pulse inside of me and for the first time i felt a warm sensation deep in my body. I had never felt a man cum so forceful or so much. After he orgasmed in me we held each other for a while as our bodies calmed down before he whispered that he should go. He pulled out of me and left me laying there. He kissed me on the cheek and left closing the door behind him and leaving me.