I opened my apartment door and let my sister in. As she shuffled past I noticed a bruise under one eye. I didn't ask. She had called me out of the blue a few hours before to ask if she could stay with me for a while, and now I was pretty sure I knew why.

Regina (I call her Reg) was a big woman -- not fat, but tall and proportionate -- an Amazon with an hourglass figure. Unfortunately, her husband was just as big. I had always disliked him, and it seems I was right to do so.

Reg slumped into a kitchen chair and held her head in her hands. I stepped forward and put my arms around her. She seemed surprised but returned the hug after a moment.

"Stay as long as you like," I told her.

"Thanks, little bro," she said.

I'd known Reg since we were 8 years old. We were the same age ... our parents, both divorcees, had married and suddenly we were family. Having been an only child up until that point, I was delighted to have a sibling, even if it was a girl.

We had gotten along well. Though she had always been bigger than me she had never used her size to win fights. The size difference was why she had always called me "little bro", even though I was actually a couple of months older than her. She was currently 6' tall and I was only 5'9".

My feelings toward her became more confusing after we hit puberty. Suddenly she sprouted boobs and her hips swayed as she walked and I couldn't keep my eyes off of her. She seemed amused by my attentions but because we had been family for half of our lives by that point she was off limits. It didn't stop me from whacking off thinking about her most nights, though.

Now, at 25 years old, we had known each other for over two thirds of our lives, though we hadn't talked much since she had married Brad and moved to the big city a couple of years ago.

She was even more beautiful now, the vision of a Greek goddess in all her glory, except for the black eye. I pulled back from our hug, quickly turning away to hide the hard-on that I had sprouted.

Since I lived in a one bedroom apartment I graciously gave up my bed to her and took up residence on the couch. It wasn't as comfortable as my bed, but it was better than sleeping on the floor.

Hm ... I had said that she could stay as long as she liked, hadn't I? Hopefully not so long that my back was mangled by the couch! Still, it was good to see Reg again. I missed her.

We had Chinese food delivered and talked about stuff, though we definitely didn't talk about why she wasn't at home with Brad. When she was ready she would tell me.

That night I awoke to the sound of Reg crying out in fear. Thinking that Brad had somehow found her here I was up in a flash, rushing into my bedroom to defend her. I was so concerned that I didn't even think about the fact that I was naked.

I stopped when I saw by the dim light coming through the window that no one else was in the room. Reg was thrashing violently on the bed, mewling and calling out, "No..." over and over.

I rushed forward, jumped on the bed and gripped her shoulders. "Reg!" I called out, "Wake up!"

A flailing arm whacked me across the cheek and I fell to the side. After my ears stopped ringing I lunged forward again, this time between those windmilling arms, and wrapped my body around hers, my face tucked into her neck.

"It's okay," I whispered. "You're safe ... you're here with me, and I'm not going to let anyone hurt you."

Slowly, Reg's arms and legs stopped thrashing. I repeated words of assurance, letting her know with soft but urgent whispers that everything was alright. I felt her finally relax.

That was when I noticed that not only was I naked, but so was Reg, and she had kicked off the sheets so that there was nothing separating her body from mine. I could feel the heat of her skin, and especially the sizeable mounds on her chest, pressing into mine.

My cock suddenly sprang into action, filling its 6 inch length with blood so fast that I was left light-headed ... or maybe it was the blow to the head? I also realized that I was between Reg's thighs.

"Mmm..." Reg sighed as she wrapped her arms around my back. Then she pulled my head toward hers and kissed me.

I was locking lips with a forbidden woman I had desired since I was a teenager! Somehow my dick got a little bigger. Its head bumped something down there.

"Mm-hm..." Reg hummed into my mouth as she opened her mouth and stuck her tongue between my lips. I felt the tip of my cock moving along soft skin as she adjusted her hips.

I'd like to think that if I hadn't just woken up out of a deep sleep, or maybe hadn't just taken a blow to the head, that I would have broken the kiss and gotten the hell out of there. But what happened, happened, and what was happening right then felt too good to stop.

I returned the open mouth kiss, my tongue dancing with hers. The tip of my cock was now someplace very warm. I instinctively pushed my hips forward. I could feel soft, warm flesh part from my insistent pressure. The wet heat of Reg's vagina was now surrounding the head of my cock.

It felt incredible! Both of us moaned at the pleasure of it. We kissed more passionately and I felt her legs cross behind my back. Then as she pulled me toward her my cock moved almost halfway inside. We gasped in unison.

I broke the kiss and started to nibble on her neck. She made pleasurable noises and I tried to pull out a bit in order to get a better angle to thrust with but her legs were holding me fast. Then she started to roll her hips.

I had never felt anything like it before. Her vagina pulled on my cock, angling it up, and then she pushed forward, angling it down. Her legs pulled me forward again and my dick slipped all the way inside her.

"Uhh!" I heard her groan. I think I groaned as well, but I was lost in the sensations. The walls of Reg's pussy rippled around the shaft of my cock, which had never been harder. Was she cumming already?

It seemed so: "Uh! Uh! Uh!" she cried out as her hips continued to roll and her pussy clasped at my cock. I realized that with these incredible sensations that I wasn't going to last!

'I should pull out!' some vestige of reason called out from somewhere in my mind. I tried to do just that but Reg's legs were still locked behind me, holding me fast. 'Oh shit!'

I couldn't pull out, and my sexy Amazonian stepsister, who I had fantasized about since I could masturbate, was orgasming hard on my dick, stimulating it to release. I had no chance. I felt the pleasure start to overwhelm me as my cock swelled up even more. 'No, no... ' I thought as another part of me said, 'Yes, yes... '

I grunted as my cum raced up my hard shaft and out the tip, injecting itself deep inside my orgasming stepsister and splashing against her cervix. I had no idea if Reg was on the pill, but she wouldn't have initiated unprotected sex if she hadn't been safe, right? Right?

Reg continued to gasp and roll her hips, her spasming channel urging more seed from my balls. Another orgasm washed over me, and more bolts of sperm-laden semen shot right where nature intended for them to go. I had never had multiple orgasms before! Reg's body was incredible!

Finally, shaking, we both collapsed. It took a few minutes for my breathing to return to something close to normal, but when it did I noticed that Reg was snoring.

Snoring? It was a guy thing to fall asleep after sex, but I had heard that sex energizes most women ... that was why they wanted to talk while I was struggling to keep my eyes open after doing the "horizontal mambo". Even if Reg was tired she shouldn't have fallen asleep right after sex...

... unless she had been asleep the whole time! Did she just fuck me while dreaming?

I suddenly felt like a total piece of shit! I carefully pulled out of her. Yep, she was still snoring. What had I done?

I covered my sister up and went back to the couch. In the morning she would either mention what we had done, or not.

It was a long night.

In the morning Reg made bacon and eggs for us. She didn't say anything about last night, making me suspect that she had in fact been unaware of our illicit coupling.

I wondered if I should ask her about birth control, but what reason could I give for asking? In the end I just left it alone. Either she was or she wasn't, and if her next period didn't arrive then that would answer the question.

I wanted to take her to a movie but she didn't want to go out. We watched TV. At one point she laid her head on my shoulder and I put my arm around her. She smelled so nice that I had to adjust the way I was sitting so that she wouldn't see my hard-on.

She made dinner as well ... spam, scalloped potatoes, and green beans. It was nice having someone in the apartment that could cook ... I didn't even realize I owned a can of green beans.

That night I was again awoken to Reg's desperate cries from the bedroom. I had slept naked again by habit, but was smart enough to approach the bed from the side this time. I timed my approach and then when she thrashed away from me I slipped into the bed next to her and rolled her the rest of the way onto her side, which actually required some force due to our size difference. I gripped her around the midsection firmly but lovingly, and got my mouth next to her ear. Again I told her that she was safe, that no one would hurt her; I wouldn't let them.

After a couple of minutes of me whispering assurances into her ear she relaxed. She smelled so good. My hand lightly caressed her firm tummy. My cock was hard again, wedged in between her buttcheeks.

"Mmm..." she moaned, reaching back to grasp my cock. I moaned at the pleasure from her grasp.

But I had to make sure if she was awake or not. "Reg?"

"Mm-hm?"

"Are you awake?"

She turned a bit to get some leverage and started to pull on my cock. "Mm-hm..." she mumbled.

I was no longer thinking with my big head, so that was good enough for me. I stretched to open the side drawer and extracted a condom packet. While Reg expertly reached back and whacked me off I ripped it open.

I pushed her hand away and got up onto my knees. I quickly slipped the lubed prophylactic onto my member and grabbed her upper leg, lifting it high while keeping her on her side.

"Mmm?" Reg sighed. I put that leg over my shoulder and lined my cock up with her pussy. The condom's lubrication and Reg's own juices helped me to push half of my dick inside her without trouble. We both moaned.

I pulled back a bit and then pushed again. Three quarters went in. It felt so good! I swirled my cock around, making Reg squeak in pleasure, and then pulled and pushed some more until I was buried all the way inside of my stepsister's forbidden depths.

I hadn't had any chance to explore Reg's body the previous night. As I began to thrust into her I reached forward and grabbed a big handful of boob. Magnificent! I had fantasized about them, and the reality did not disappoint.

I continued to fuck my beautiful, possibly sleeping stepsister, taking my time. With the condom on I wasn't on as much of a hair trigger as the previous night. I went slow, then sped up, and then thrust only the head in and out quickly, making her gasp. I lightly tweaked one of her nipples. Finally I pulled almost all the way out before embedding myself as deep as I could inside her. I continued the long thrusts, and before long I could feel Reg cumming. Her pussy gripped my cock -- squeeze, squeeze -- all along its length. It was incredible how she could do that!

Once Reg stopped cumming I moved back into the missionary position, easily sliding my cock back into her. I wanted to kiss her again. As our tongues intertwined I could feel my orgasm approaching.

Not having to worry about making her pregnant this time, I enjoyed myself and let go, thrusting myself as deep inside her as I could. My cock throbbed, filling the head of the rubber with my seed.

When I could catch my breath again I carefully slipped out of her and used some tissues from the side table to clean myself. I was about to toss the used rubber into the trash when I heard Reg snoring again.

Ah crap. Once again I wasn't sure whether she had been awake or not. If she hadn't been awake and later saw the rubber in the trash then there would be some difficult questions. Instead, I buried it under some stuff in the kitchen garbage and went back to the couch.

In the morning I gave Reg a peck on the cheek as I went off to work. She seemed happy, and again made no mention of our nocturnal activities.

When I got back home she had cleaned the entire apartment! My bathroom sink had been practically caked in grime and now I could see the original white of its porcelain. Yes, there were definite advantages to having my sister here: good cooking, cleaning, and ... lover? I still didn't know if she was aware of what we had done the last couple of nights, and if she wasn't I certainly couldn't tell her or she'd think I had raped her!

Had I raped her? Both times she seemed to enjoy it ... you can't rape the willing, right? Right?

I woke up as I had the previous two nights, hearing my sister in distress. I had worn my boxers to bed so what had happened before wouldn't happen again.

As I made my way into the bedroom I calculated a good angle to approach Reg to calm her down. I didn't want her to smash me in the head again but I definitely didn't want her nightmare to continue ... she sounded desperate!

This time she had managed to rotate her body 90 degrees so her head was near the side of the bed. I approached that side, knelt down so my head was close to hers, and again told her she was safe, that I would make sure of it.

She wasn't calming down. I had to touch her so she would feel assured. I leaned forward and pushed my mouth to hers, upside down like in the Spider-Man movie.