Sis stood up from the bed and unlocked the bathroom door. After picking up her clothes she opened the door and stepped through. With a smile, she clicked the door shut and was gone. I just laid on my bed, still floating on a cloud of euphoria. 

My body was buzzing all over from what had just taken place. My fingers slid over goosebumps on my hips and to my dummy cock that still throbbed, fully erect. I felt the cum on my balls. Nothing could compare to what I was feeling at the moment. 

The ceiling fan spun in a blur above my body. The wash of created breeze cooled my nakedness.  I felt the air fill my lungs with each breath. I could see my chest bounce with each heartbeat. My nerves buzzed with a new sensitivity. 

I woke at one o'clock in the morning. I didn't know what time I had dozed off. I sat up on the bed, needing to pee. My fingers felt the sliminess of the stale cum on my flaccid cock. I needed a shower too. Pushing myself up from the bed, I opened the bathroom door with my clean hand. 

I shook the water from my hands into the sink then turned the faucet off.  Next, I turned the shower on and waited for the water to heat up. My bedroom door was still open and I didn't bother locking Sis’s. I figured, ”What was the point?”

The hot water wetted my hair and ran down my back. The steam filled my lungs and woke me fully. I soaped the bath sponge and cleansed my body of the remnants of earlier sex. I was lost in the soothing heat of the shower. 

Startled by the sliding of the shower door, my head jerked up to see who was intruding. Sis stood with one hand on the shower door and the other on the wall. Her eyes on the water running from the end of my dick. 

”What are you..,” I stammered until she cut me off.

”Can I come in?”

All I could do was watch her step into the shower and slide the door shut. 

”You woke me up,” she smiled, ”You make a lot of noise.”

”Sorry,” I said as she stood under the stream of steaming water.

She took the sponge from me and put more body wash on it. Handing it back, she asked, ”Can you do my back?”

Sis turned around and put her hands on the shower wall, arching her back. He feet we're a bit more than shoulder-width apart. Bubbly suds ran from the sponge and over my hand, dripping to the tile floor. Sis looked back over her shoulder and wiggled her pretty ass, ”I'm ready.”

Of course, my cock was at full attention again. She turned back to the wall, still slowly wiggling her ass. I took a step closer, staring at her lower back, watching the trail of suds run down between her cheeks. 

She was built like a gymnast, so fucking sexy. Her legs were muscular in a feminine way. Her ass could only be described as amazing.  My feet were between hers as I made small circles on her lower back. My other hand was busy playing with my cock.

Sis looked over her shoulder again, ”I think that spot is clean.”

I took her hint and started to rub the sponge higher. My cock was only inches from her ass but I stepped forward. I heard my sister moan as my cock pressed against her pussy. Leaning forward to reach her shoulders, I put more pressure against her sex. She didn't protest verbally, but  I felt her body cringe. 

”What's wrong, Sis?” I asked, ”Did I hurt you?”

She looked at me over her shoulder and said, ”No, Terry. It feels good. I just think we shouldn't go all the way. I mean, you are my brother.”

I shook my head in agreement, and let some of the pressure off her pussy. I didn't want to stop but I really didn't want her to get mad. My cock was still in contact, but not in danger of slipping in. Grasping it with my hand, I slowly slid the head side to side and back and forth. She moaned as I continued my motions. 

Somehow, I had the presence of mind to continue rubbing the sponge around her back. My hips slowly worked my cockhead back and forth against her sweet mound. She trembled as her hands steadied her balance. She had started to match my movements, pushing herself back against my cock. 

”Just the head?” I asked sheepishly. 

Her head quickly nodded approval. 

I took my cock in hand and rubbed the head up and down her young slit. After a few seconds of that, I pushed the first inch of my hard member into her. Her knees buckled and I put my free hand under her belly to steady her. We both stood still and enjoyed the feeling. 

”Don't go deep, please.” Sis moaned.

”No, I won't, Sis.” I assured her but my desires mounted. I had to try and control my natural instincts. I pulled my shaft up and felt the head slip out of her. She shook as I pushed my hips forward, my cock sliding up her ass crack. I pressed my pelvis against her ass, trapping my cock between her and myself. 

Sis wiggled her ass against my cock until I pulled back. Grabbing my shaft I pressed it into her again, just the head. Slightly rocking my hips to create motion, I felt her buckle again. 

”Fuck,” she growled, ”This feels amazing.”

Sliding my hand from her belly, I gripped her hips with both hands. The same slight movement of my hips was driving me to orgasm. Sis slipped one of her hands from the shower wall, sliding it between her legs. Her fingers explored her pussy, stretched by the head of my throbbing cock. I heard her panting obscenities as I barely moved my cockhead at the opening of her pussy. Her fingers explored the shaft of my cock and filtered over my balls. 

”I'm going to cum, Terry, ” she moaned.

I quickened my efforts, trying to keep a shallow depth. Sis started to shake as her orgasm washed over her. She had to replace her hand on the wall. My motions were erratic at best. Her pussy became so wet from her orgasm. I felt my cock slip a bit deeper. Sis didn't protest. 

I worked in and out of the new depth, trying to maintain control. I had never concentrated so hard. It was only an inch and a half or so but I wanted so much more. I felt my sister slip her hand behind my ass. Thinking she wanted to grope me, I continued my efforts but she pulled me with her hand. 

That was all the encouragement I needed. I pushed hard, plunging my stem deep into her tight young well. My first time in a pussy and it felt great. My balls rested against her clit as I devoured the moment.

”Fuck me, Terry,” she begged. 

I let nature take over. Both hands on her hips, I plowed her tight pussy. My strokes were long and deep. I felt every inch of her sugar walls gripping my shaft. 

Cumming twice earlier today was the only reason I hadn't filled my sister with cum by now.  I fucked with purpose and determination. 

I really wanted to feel her cum on my cock before I was done. I pounded. Her pussy was so tight, I could hardly hold back. Gritting my teeth, I pounded. 

”Oh,” Sis moaned, ”Fuck, I'm going to cum again.”

I fucked her hard. My hips you smacked against her ass, making a slapping sound. My hands slid up her body, squeezing her tits. Her nipples pointed into my palms. One last deep, hard thrust and my cock exploded inside my sister. She trembled in orgasm as I pumped my seed deep into her womb. 

We slid slowly to the shower floor, the water, now cold, spraying our spent bodies. 

”Did you cum in me?” she asked.