Wife's Sister Wants Another

Her eyes shot open and she screamed in pleasure, shaking underneath me as she came around my cock, which I just held deep inside her and let her grind against, riding the waves of pleasure. When she started to slow down a bit, I took over, and finally began thrusting in and out of her. SHe just locked eyes with me, slowly coming to her senses, and matching my rhythm with her hips. After all this buildup I knew I wouldn't last long, and could already feel the familiar tingle in my shaft. Having brought her to two good orgasms already, I wasn't about to hold back, and picked up my pace, resting my weight on one hand while bringing the other up to grab her breast. She moaned -- maybe for my benefit, but i'll take it -- and i told her I was getting close. Behind her eyes she had a look of raw animal lust, and started talking to me in a throaty whisper.

"Yeah, you're close? Are you close to shooting your cum into your wife's sister?" I dont' know where this side of her came from but it was turning me on like crazy. "Are you gonna fill my fertile womb with your seed?" My eyes shot wide and I looked at her -- though I never slowed my thrusts -- and she gave me a mischievous lustful smile and grabbed onto my hips as she continued. "That's right, it's a perfect time for me, and my husband doesn't want to give me another baby, so I figured I'd enlist your help. Who knew you'd be so good at it?"

My head was spinning but my hormones -- and some animal part of me intent on spreading my seed -- had fully taken over. I could feel my balls contracting as she rolled her head back in pleasure. "Oh God" she moaned " I can feel you getting harder, you're getting ready to fill me up aren't you, that's it, shoot it all into me, I want to feel every fucking drop of cum filling me"

That was it, I gave one final thrust as hard as I could and held myself as deep as possible inside her and let loose what must have been the biggest load I had ever released. I just kept pumping and pumping, hearing her moan as each spurt filled her more and more, before I finally just collapsed on top of her, her breasts mashed between us as we both struggled to catch our breath.

We just lay there together for several minutes. Post-nut clarity was throwing a lot at me -- not just cheating, but with my sister-in-law, and also possibly knocking her up, unless that was just dirty talk? THinking about that last bit I realized my softening cock was still inside her, holding everything inside.

I finally rolled over and looked at her. She smiled at me, and put her hand on my chest. So at least I didn't think she was regretting our tryst.

"So," I finally asked, "were you like, serious about getting knocked up again?" MIght as well tear the band-aid off that one.

She rolled on her side facing me, and looked at me for a beat. "I won't like, expect anything from you. I know you don't want kids and I'm certainly not about to blow up my sister's marriage. But I was absolutely serious. If my asshole husband isn't gonna give me another kid I can' imagine another person I'd rather knock me up."

I looked up and down her body, and felt my exhausted cock twitch and start to grow. She glanced down and smiled at me. "Looks like he agrees."

I just laughed. "Who am I to argue?!" as I leaned in to kiss her.