I was spending the night in a hotel after a wedding. My girlfriend and I had an adjoing suite with her parents. After we retired for the night I woke up suddenly to the soft moans of my girl. From the hallway mirror I saw her getting fucked from behind. The man had a huge cock. It was her dad. She told me that incest porn turned her on. Now I knew why. I kept quiet and watched. Dad fucked her good. His erect cock was over ten inches long and thick as a can of soda. She came three times before he unloaded his seed on her face. Later on after I read her diary, I found out that her dad started molesting her since she was 7.