I started with her bra. I transferred her wrists to one hand and then used my free hand to pop open the front of her bra, something I'd learned to do well with my two other sisters. Surprisingly, Serena let me. But as I freed her terrible twosome to the air, she freed one hand and grabbed my hair. To my surprise she didn't pull it out of my head. She pulled my head down to her nipple and sort of lifted her torso at the same time to mash my mouth against her breast.
"Cum, Stevie boy," she purred, "Cum for your hot big sister, shoot that big gun at me."
That was it, I was tired of our impasse. And, if she had her way, I would indeed cum in my pants. She looked incredibly fucking hot under me, those wonder tits thrust up at me, her makeup getting smeared around her pretty face, that flat hard tummy.
So I let her hands go and in one quick movement I rocked back on my haunches and grabbed her jeans zipper and pulled it down. She tried to wiggle out of my grasp at that point but it was too late. I pulled down hard on her waistband even as I lifted her ass off the ground and her jeans dropped around her knees. Now I stood up, still gripping her pants and more or less holding her suspended upside down.
She tried to crawl away from me, kicking out of her pants as she did. I lowered my own shorts and as she squirmed away on her hands and knees, I dived and landed on her back. My eight inches of hard bad boy cock landed right in the crack of her ass.
She grunted and flailed but I had my full weight on her backside and she couldn't wiggle out from under me. Then she did something unexpected. She lifted her ass off the ground and spread her legs, letting the head of my prick nudge up against her pantie covered labial lips. Completely soaked panties.
I reached down and pulled them aside, putting my cock into the slit of her pussy, feeling the wetness of it, feeling it open slightly in response.
But she wasn't giving up that easily. She began to struggle mightily beneath me, wriggling and wiggling and I had all I could do to hold her. Finally, with her twisted around on her back now, I got my arms under her thighs, pushed them against her shoulders and used my full two twenty to hold her down. My prick was right at the portal of her pussy, even penetrating slightly because of the copious quantities of juice oozing from inside her.
She looked up at me. "Well, big boy, you got me," she smiled wickedly as she said this. "Do you know what to do now?"
I did. In one powerful thrust I sank the full shaft of my raging hard rod all the way down to the hilt, eliciting a very sexy grunt from her as I bottomed out and rocked her ass. Her tits bounced. She reached her hands around and grabbed my ass cheeks to hold me inside her.
"Don't cum too quick there, Stevie boy," she said, evil in her eye, "you're fucking your big sister, you bad little boy."
Wouldn't matter if I did. I'd stay hard anyway. But I didn't. Not with that kind of challenge. Instead I decided to make her cum first. I reached a hand around and stuck a finger into her ass. In response she did the same to me. I was fucking her slowly and as strong as I could, holding myself above her with one hand, letting her get a good look at my powerful, hairy pecs, ripped abs and thick long cock, and reaming her butthole with a finger at the same time.
She tried to match me thrust for thrust as best she could from that position, and she really was working over my own anus with her finger.
"Suck on my neck and nipples, Stevie, while you fuck my snatch," she growled, and it was clear this was a contest to see who could hold out the longest.
I had a certain advantage. I'd recently learned a thing or two about fucking from my other two sisters. I knew Serena could cum multiple times to my few. I let myself fall sideways so I could bring both hands into play. Lying on our sides now we could both hump against each other and she put her free hand on my balls. I put mine against her clit. Then I began to talk dirty, something I'd learned from Krista.
"You are a wet dream, Serena, the kind of woman guys want to fuck just looking at her walk down the street. You are the hottest fuck most guys could ever dream of, a fucking sex bomb that can explode in a fountain of cum, can cum all night, and I could die inside you and die happily. I will gladly shoot the last bit of spunk from my balls into your sweet, tight, hot, soggy, sloshing cunt, and drain every last cell in my body inside you. You are the most fuckably horny girl walking this planet. I am just a fucking machine, one big walking erection around you."
And so I sped up my thrusts, drilling into her well lubed cumhole, and mauling her tits, kissing her neck and stroking her clit relentlessly.
"Stevie, you asshole," she croaked, and then she came with one long moan, her vagina swelling up and then a floodgate opened inside her and washed wetness all over both our genitals and onto the floor. She was a squirter. My sister was a squirting messy soggy cum queen and I felt my cock start shooting inside her like a cum loaded automatic pistol, blowing one bullet of spunk at a time into her flooding cunt. As she felt me cum, she rolled over on top of me, let out another groan and came even harder, her body going stiff then she began convulsing spasmodically, thrashing so wildly I had a hard time holding onto her. It seemed to last forever, even when we both were completely drained, her vagina continued to clutch at my hard penis, sucking the final twitching spurts of spunk out of my balls.
We lay there a few moments, gradually regaining consciousness. She spoke first.
"Don't think you're done, Stevie boy," she whispered.
I pulled out and lowered my face to her fully fucked, still oozing and spasming pussy. I licked and sucked her entire crotch, then I crawled up her torso and kissed her deeply, letting my tongue lavish hers with our combined juices.
"Round one was a dead heat," I whispered.
Then I moved my cock up to her tits, dabbed the last drips of cum from the slit onto her nipples. She squeezed her two beauties together and I began fucking between them.
"You're still a dick, little brother," she said as she watched my dickhead push up from between her titillating titties. She reached her tongue down and licked it.
We spent those three hours fucking in every way we could imagine. We took a few breaks to drink some beers and it turns out my sister can really down them. In fact we were getting a little drunk toward the end when she leaned over the couch and wagged her ass at me. I poured beer down her crack and nuzzled my cockhead against the tiny tight rosette of her anus.
"Fuck it, little bro, fuck my ass, if you still got it in you."
Well, it took a little effort, but I did get my eight inches inside her ass. She reacted by leaning forward on the couch cushions and blowing out, huffing and puffing. She winced as I began fucking, and her face showed the strain of taking all that cock inside her butt. But she was not going to give in and quit. And the beer made it easier, less painful. As her anus expanded, the pressure released a little and she got into it. She, as she had all night, fucked me back as hard as I fucked her, pushing her butt back to meet my every thrust. She reached beneath her and fingered my cock as it penetrated her butt. This time I came first. She made me cum.
"Fuck me, Stevie boy, fuck my tight, virgin ass with that big boy cock. Fuck my hard body, my big titties, round ass and pretty little pussy. Fuck your big sister, Stevie, make her your nasty little cum doll, make her dream about your big cock as she fingers her sweet cunt in the shower, as she jams her dildo into her own ass at night in bed, thinking about how that cock feels pushing inside her butthole, cumming all over herself and whispering your name. Cum little bro, cum on me, cum in me, cum all over my body, shoot your sperm onto my face and into my mouth, drown me in a flood of jiz. Oooh, yes, you fuck me sooooo good."
And that cum seemed the most powerful, coming from deep inside me, a last explosion, watching her magnificent ass wiggle so obscene and lewd against me as my dick slammed as far up her anal passage as it would go and emptied every last bit of spunk I had left into her intestines. I spat and gargled and sweat dripped onto her back as the top of my head blew away and on the edges of my vision I saw sparks of light. She finished by stroking herself to another orgasm, continuing to hump her smooth, white, muscular butt cheeks against me even as my cock popped out of her, rocking back at me as if she was on auto hump, unable to stop fucking me. We ended up tangled up on the floor, limp, breathing hard, both of our hips still twitching occasionally as the fucking motion gradually stopped.
"I win," she panted, "I made you cum last."
I conceded, happily.