Last night my wife went to bed about a half hour before I did. Once I crawled into bed she looked like she was asleep so I leaned over and kissed her and then turned over to get comfortable. She scooted over and cuddled me closely from behind like she usually does. I started to doze but noticed that she was cuddling more closely than usual and that she had draped her top leg over mine. She was moving her leg up and down a bit, but nothing too obvious. I woke up a little more, wondering if she was horny. The movements were subtle though and it seemed like it might be a little involuntary, like she was dreaming. A few minutes later though, I felt her hips pushing into me. At the angle she was at, her clit was right on my tailbone. Again, her movements were subtle, but at this point it seemed obvious that she was grinding into me... This woke me right up! I reached behind me and grabbed her sexy ass and pulled her hips hard against my back, holding her clit and pussy into my tailbone area. She moaned as I did this and started grinding harder and more obviously.
This continued for about five minutes when I finally turned over and kissed her. She returned my kiss aggressively, driving her tongue into my mouth. She pushed me onto my back and straddled me, both of us still in our pajamas. I was hard and she positioned her clit over my bulge and proceed to grind on me. I reached both of my hands into her panties and grabbed her sexy ass, holding her down on me. She was moaning and breathing heavily while I spread her ass cheeks and bucked my hips into hers to maximize the friction she was feeling. I moved one hand off her ass and up under her shirt, lifting it and exposing her hard nipples, pinching and teasing one while she bucked against me. In another minute or two she lost control and started furiously grinding on my bulge, moaning that she was going to cum. A few seconds later she did and then rolled off me.
"Why didn't you tell me you were so horny?" I asked her.
"I wasn't," she replied, "until I cuddled up next you. You woke up my pussy and I couldn't help myself."
With this she reached down to my bottoms and pulled out my hard cock.