I knew when I was watching a porno with my wife and then an interracial scene came on. My wife wanted to skip it because she wasn't attracted to black guys but I always secretly liked interracial porn better, so I asked her if we could watch it. She looked at me confused but agreed. When the black guys huge penis flopped out my wife gasped and she said "oh my God, I didn't know penises could get so big". I felt a rush of emotions, jealousy (she didn't gasp when she saw my cock), but really turned on, angry that she seemed to like it this much, but I wanted to continue watching it with her, sad that she was as wet as she was, but I wanted to see her like that again. I ordered a big black dildo and when it arrived I told her I had a surprise for her. I put on her sleeping on her and took out the dildo. I licked her pussy and sucked her tits to get her started, then I lubbed the big black dildo and slid it inside her tight pink pussy. She gasped and asked "what is that"? I pulled off her sleeping mask and she looked down then looked at me with a shocked expression. I started pumping it in and out, and asked her if she likes how that feels. She yells yes and then grabs my shoulder and starts shaking and screaming. She had one of the best orgasms in her life and it only took about a minute of penetration. I've never made her cum on my dick like that before. Her pussy was wetter than I've ever seen it. She grabbed my cock and said "this must've turned you on. You're leaking cum". There was so much precum it looked like I prematurely ejaculated. I fucked her pussy and lasted about 30 seconds before I came. That's when I knew I wanted to be a cuckold.