My parents had gotten divorced when I was quite young and my dad remarried not long after that. His new wife had a daughter, Melissa, who was a year older than me. We basically grew up together as brother and sister even though we weren't blood related.

Mel, as we called her, was a tomboy through and through. She played with other boys in the neighborhood and almost never wore dresses or skirts. She wore her hair short and, if you didn't know her well, you would have sworn she was a boy from a distance. We were always good friends and we thought of each other as siblings, referring to each other as "brother and sister".

As we grew older and reached puberty, Mel maintained her boyish outfits and I never gave her female form another thought until one day just a couple of months shy of her 19th birthday.

I had woken up late for school and rushed to the bathroom I shared with Mel to pee and brush my teeth...no time for a shower, I thought. I should have knocked since the door was shut but being late and in a hurry, I simply turned the knob. It was unlocked and as I stepped in. Mel had just gotten out of the shower and was full frontal nude in front of me.

My cock instantly got hard as we both stared at each other. My eyes lowered to her very ample breasts that had dark areolas and large nipples that seemed quite erect. I continued down her body and saw a dark triangle of untrimmed pubic hair. Her flat belly and well proportioned hips gave her a sexy hourglass figure that I had not noticed before.

Mel stood shocked as her eyes went down my youthful, toned body. I was just in my tighty whities and my boner was sticking straight out. I'm not porn star worthy but with a solid 7.5 inches, my erection was very noticeable. Her wide open eyes stayed on my dick. Neither of us moved nor made a sound.

The few seconds that we stared at each other not knowing what to do until I broke the tension by apologizing profusely and headed back to my room. My cock was extremely hard still and being the horny 18 year old, I jumped into bed and started to jerk off. I had a couple of girlfriends that I had played around with but none had a body like Mel and I came within a minute of pleasuring myself.

Embarrassed, I sheepishly left my room when I heard Mel leave the bathroom and got ready for school. We both attended the same high school so the walk there was a little awkward. We remained mostly silent and parted ways as we entered the building.

We didn't mention that incident though she often was the center of my masturbation fantasies for the next couple of months until things came to a crescendo on her 19th birthday. One of her friends had a boyfriend that made fake IDs and she ended up bar hopping for the evening after our family had celebrated at home.

Dad and my step-mother went to bed and I stayed up late watching television. I heard Mel come in around 1am. She was clearly drunk given how she stumbled about. I was the good brother and assisted her so she wouldn't wake up our parents. Putting my arms around her, she said, "I have something for you." Mel reached into her purse and brought out a small vodka bottle. "Want to have a drinky drink with your big sis?" She flashed a drunk smile my way.

I smiled and responded, "That would be fun but we should go to the basement so mom and dad don't hear us." I had a few drinking sessions with my buddies in the past and figured it would be fun to join Mel in her festivities.

I managed to get her downstairs and quickly grabbed some shot glasses from the bar on the far side of the basement.

"You have to catch up with me first!" she shouted and I hushed her right away for being a bit too loud. Mel giggled and I downed a couple of shots. She laughed some more and poured two more once I had a minute to settle.

"Fuck, Mel. You're going to get me wasted..." I playfully scolded her while downing those drinks, too. "Let's do one together, sis." I filled the two glasses and we picked them up for a cheer. "To more drinks!" I said.

"To more unlocked bathrooms!" Mel unexpectedly said and shocked the crap out of me. She clinked our glasses and downed the vodka. I sat there with my mouth open not taking a sip. "What's a matter, little Jonny, or should I say big Jonny! Take your shot!" Mel looked down towards my crotch and back up to my eyes as she giggled more.

I downed my shot and before I knew it, Mel leaned into me and started to kiss me deeply. Our tongues swirled in each other's mouths and our hands started to roam our bodies. She was quite aggressive and placed her hand onto my hardening cock, squeezing until it reached it's full size. My hands went to her breasts and I fondled my sister's chest while we both moaned and panted in unison.

We made out for several minutes as my hands found their way under her shirt and played with her erect nipples. She leaned back and gave me full access to her big tits. I slid her bra up and started to suck on my sibling's nipples, alternating between each one. Mel's hips pressed into me and soon we were dry humping our aroused genitals as we continued to make out.

I went down her body and with no resistance, I unbuttoned her pants. She lifted her hips up and I got a full view of my sister's pussy when I pulled her pants and panties off. Her legs were spread wide and her hands held her pussy lips open inviting me to eat her out. I wasted no time in diving towards Mel's wet sex. She tasted better than my other girlfriends and I licked her up and down, spending quality time on her clit even rimming her ass for a bit. Mel grabbed the back of my head and fucked my face until she came hard. Her groans were muffled as to not wake our parents.

My sister pulled me up and licked her juices off of my face. My cock had never been harder. "Fuck me, Jonny," she whispered in my ear.

I clumsily removed my pants and my cock was poised at her cunt. I had a last minute ping of responsibility since I didn't have a condom. Mel could sense my reluctance but reassured me, "Don't worry, I'm on the pill." That was all the go ahead I needed, and I sunk my cock into my sister's pussy. She was tight but extremely wet and I didn't have much issue going balls deep into my sibling.

I started pumping into her while she laid on the couch. Sucking her tits and kissing her, I soon was building up for a major climax. Mel bucked her hips against me and within a few minutes I started to ejaculate inside my sister's womb. She hadn't cum from us fucking yet as my cock started to deflate and slipped out of her. I was going to fuck her again after I recovered but I had to stop.

At that moment, we heard footsteps upstairs and immediately broke apart. Mel grabbed her clothes and jumped to the basement bathroom while I scrambled to put my pants on.

"Are you still up, Jon? Is Mel home yet?" my dad shouted from the top of the stairs.

"Yep, dad. I was just about to go to bed. Mel's down here in the bathroom, too. We're heading up soon."

"Ok, great. Have a good night and don't forget to turn the lights off."

Fortunately, he never came downstairs as I was still zipping up my fly and realizing that we had left a big wetspot on the leather couch. I grabbed some tissues and cleaned up my semen and her juices as Mel came back from the bathroom.

She closed the distance with me and pressed her body against me. "That was close. Next time, we'll make sure they aren't home." With that, Mel gave me one last kiss and headed to bed.

I didn't have to wait long before our parents had left us alone.

If you'd like to hear about that dirty time, please leave a comment!!

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