I've wanted to ** my wife's sister, secret

She is 6 years older than my wife and a single mom of a 9 year old boy, and a nurse. The other day I had to take something to her house when she was at work and her son was out of town visiting his dad. I explored her bedroom and her panty drawer. As conservaive as she appears, she had some really ** stuf in there! Then, I found some ** that she had worn, and I couldn't help but smell them. Then a thought occurred to me.....how cool would it be to be able to say that I've been naked in her bed? I slipped off all of my clothes and crawled into her bed, planning to ** with her soiled panites on my face and then get out quickly. Everything changed when I heard the door to her place open! Being a nurse, sometimes she gt sent hom early and this had happened and I was obviously busted! I pulled the covers over my head, but there was no hiding it as my clothes were all over he bedroom floor! She came into her bedroom, saw my clothes, and I didn't want to scare her, so I had to give myself up. I pulled the covers off of my head and sain "Hi, I'm busted!" I explaned to her that I had brought something over to her house, let myself in with the spare key, and that I had been infatuated with her for a long time and I would leave and promised to never do anything like this again if she would just PLEASE, not tell my wife! She stood there and thought for a minute, then she said she'd not tell my wife on one condition, and one condition only......I asked what? She said "It's been YOUR fantasy, I want you to act it out with me." I said what do you mean? She proceded to take off her nursing scrubs, in front of me and there she was in a bra and **! As scared as I was, I had the most raging hard-on imaginable! It gets better, off comes her bra, and she playfully throws it at me on the bed. Then the **, down to her ankles and she steps out of them. She walks over and crawls under the covers with me and on top of me! I'm in shock, but I know it's been years since my ** sister-in-law has had the bone. Her ** is restin on my abdomen and she leans down and plants a passionate kiss on my lips, our tongues exploring each others mouths. She starts, to slid down and just as my rod starts to penetrate her sopping slit, she says "Oh, man, we just can't do this!' "Not only is this wrong, I'd be betraying my sister, it a huge sin. And I'm not even on the pill." I said to her "But it's SO exciting, isn't it?" With that she began to kiss me anamalisticly! My hands explored her bare **, smaller but perkier than my wifes, and her cute ** and ran through her dark brown hair. Finally, I just had to taste her! I flipped her onto her back, slid my face down, and dove tongue first into my sister-in-law's tasty **!
I tongued her for 20 minutes and she had 6 or more intense **, I lost count! I began to kiss my way up her beautiful body, stopping to ** on each breast for a few minutes. We began to kiss passionately again as I slid my ** up and down on the outside of her slit. It slid into her once, and she said "No, remember what I told you, I'm not on the pill, and I'm ovulating right now!" We continined to kiss as I continued to rub mmy ** up and down on the outsde of her **. She was starting to go mad as every once in a while, my ** would slide insde her for a stroke or two, before I'd pull it out. One time it'd be in there for one stroke, the next time two strokes, then four, then eight, finally, I kept it in there and not only did she not protest, but she wrapped her legs aoround me and said "Oh, just please ** me! ** me hard!" I quickly obliged! As I ** her so intensely she screamed "Oh, I've wanted to ** you for so long! I don't care about anything else right now as long as you're ** me!" My bare ** pistoned in and out of my sister-in-law's sopping, unprotected ** and I didn't care at that moment either. Next she shocked me by saying "Oh ** in me! ** me hard, and ** in me! ** in me and make me pregnant!! Do it now!!" With that, I exploded inside her