Unintended Results

"God, you're actually perving on me a little, aren't you?" Zoey said.

I shrugged as noncommittally as I could. "It's not exactly unpleasant."

"Yeah, I bet it isn't. You wanna know something though?"

"What?"

"Well, maybe it's just 'cause you interrupted me before I could finish getting off and I'm still horny, but it's not all that unpleasant for me either."

"That kinda kills my bargaining position."

"Mm-hm, I guess it kinda does. Are you saying you still think I should put some pants on?"

"I might be wavering a little," I admitted.

The corner of Zoey's mouth twitched upward in was not quite a smile. She moved from where she was sitting at last and I assumed she was going to give in, until she turned and sat herself down in my lap facing me. Her hands took mine and placed them on her butt before settling on my shoulders.

"There's some upsides to my current outfit you know," she said softly. "If you thought about it hard enough you might find you agree with me."

I didn't disagree, even without thinking about it for very long. What confused me was how my sister seemed to be doing something very similar to coming on to me. Granted I'd started it, but that hadn't initially been my intent.

"You have a nice ass," I said, for lack of anything better to say.

"Thanks." She leaned in closer to my ear and spoke barely louder than a whisper. "Whatever happens, we probably shouldn't say anything to Mara okay? At least not 'til we figure stuff out for ourselves. She'll just think she can push us into whatever she wants."

"That's probably a good idea," I agreed.

I had been getting hard already from touching Zoey, but that process accelerated greatly when she started grinding on my lap. She had to be able to feel my erection as it stiffened enough to make contact with her butt, and if anything it only seemed to encourage her.

Moments later Zoey confirmed that she knew exactly what she was doing when she undid the front of my pants and reached in for my cock. She had to shift her body around in kind of a weird position to remain in my lap while doing so and I found myself having to lean back to give her more room. It just seemed easier to give up and lie back on the bed, so that's what I did. I figured Zoey pretty much had things under control anyway.

"I don't think we should go too far," she said, taking advantage of the space I gave her to lean farther forward and brace herself with one of her arms. "But I'm gonna try and make this feel good for both of us. It's not really worth the possibility of disaster if we don't get anything out of it, right?"

Her hand released my cock, and was replaced by her panties as she resumed grinding on my crotch. It was much more purposeful now, much more focused on results beyond just getting me aroused. As good as it felt, I could imagine her bare pussy feeling so much better sliding up and down my shaft, but without Zoey's panties between us there was too much risk of accidental penetration. It was probably for the best to avoid that possibility.

In her position Zoey's boobs were almost directly above my face and I assumed, given the circumstances, that touching was okay at this point so I started pulling her shirt up to expose her stomach. She didn't say anything, but she did smile a little when I reached her bra, more than enough confirmation for me that I had her permission to continue. I couldn't get her shirt all the way off without basically pausing everything while Zoey lifted her arms, so instead I opted for rolling it up above her breasts where it seemed like it would stay put. Then I began working on unhooking her bra.

"I hate to say it, but I think I am starting to sort of see Mara's point," Zoey said. "This is kinda hot in a fucked up sort of way."

"Emphasis on fucked up. But yeah, I know what you mean. My brain's so confused about you being hot and on top of me, but also being my sister. It keeps telling me I'm doing something wrong, and somehow that feels good."

"Mm-hm, weird isn't it?"

Once I got Zoey's bra off I had easy access to her breasts and I cupped them in my palms, I was now able to feel them so much better than I could through her clothes. It was almost impossible to believe how many years I'd gone with no desire to ever see them now that I knew what I'd been missing, but of course things had been different then. It was just something I'd have to accept, that I might not ever be able to see my sister in quite the same way anymore. Whether it would make things better or worse overall, I didn't yet know.

For several pleasure-filled minutes the entirety of my world was Zoey and her body and the way parts of it felt against mine. I could see her of course, and hear her breathing, but increasingly my senses were focused on my cock where the constant motion of her panties was working for me better than I would have expected it too. It wasn't as good as actual sex or anything, but it was definitely a step or two beyond masturbating.

It seemed Zoey wasn't entirely in a agreement with me however.

"This isn't quite doing it," she said, just a hint of frustration in her voice.

"Okay, do you want to try something else?"

"I think...." She looked at me, searching my eyes. "I think maybe if I put it inside. Just for a little bit, just long enough for me to get off."

"I don't know, I'm kinda getting close and... you know."

"I know, but you can just warn me when you need to pull out. Unless you're not ready for it, 'cause I know we said we weren't gonna go that far."

She didn't stop moving as we talked, though she did slow down quite a bit until her hips were just rocking gently back and forth. I took a moment to think about my answer, but honestly I knew I'd go along with whatever she wanted. Partly because I was too horny to say no, and partly because, more than anyone else who could have been with me at that point, I trusted her. If she thought it would be okay, then so did I.

"Okay, do it," I said.

Zoey nodded and reached down to her panties, fumbling with them until they were out of the way and my cock was pressing directly against her pussy. She was more than wet enough for me by now, we'd been through the equivalent of some overly extensive foreplay after all, which was good because she wasn't in a particularly good position to guide me in and we had to rely somewhat on her body accepting me on its own.

Once I was about halfway inside, my sister's pussy abruptly tightened on me and a look at the expression on her face suggested it was probably an involuntary reaction to what she was feeling. She appeared to be losing some of the control she'd had up until now and was giving in more to her instincts. There was a sort of an aura of primal lust to her, something I didn't think I'd ever seen before on anyone.

I lay there and let Zoey fuck me, intending to let her go as long as possible even though, as I'd already told her, I didn't think I'd last all that long. Particularly with the way her pussy continued to grip me so tightly at semi-random intervals. There was only so much I could take.

"Maybe we should stop soon," I said, hinting that I was getting close.

Zoey seemed to ignore me at first, but after a moment she acknowledged my statement.

"Not yet," she said.

"I can't last that much longer," I warned her.

"Just a little more."

I tried my best to hold off my impending orgasm, but there really wasn't all that much I could do about it. I had no control over the stimulation I was getting short of pushing Zoey off of me, and force of will alone wasn't going to go nearly far enough.

"Zoey!"

She ignored me for real this time, and seconds later I came while still buried in my sister's pussy. I didn't feel bad about it right away, mostly I just got an extra rush from knowing I'd just done perhaps the most wrong thing of my entire life, and the fact that she didn't seem upset about it either helped calm any belated guilt before it had a chance to make itself known.

I assumed Zoey must have cum right after I did judging by her reactions, though she didn't make it obvious. Mostly I was going on her lack of frustration as she lifted herself off me enough to let my softening cock out of her pussy. I doubted she'd look so happy if she still needed to get off.

It was while we were just starting to recover and think about straightening ourselves up that I happened to notice something out of the corner of my eye. As I turned my head it quickly became clear what it was, or, more to the point, who it was.

"Mara? How long have you been there?" I asked, too confused to muster more than a slightly puzzled query.

Zoey looked too as I spoke and sighed heavily at discovering her roommate watching us.

"Godammit," she muttered.

"A couple minutes, maybe more," Mara said. "I didn't want to interrupt."

"Of course, I'm sure it was purely for our benefit," Zoey replied sarcastically. "Just like that text you sent Adam."

"Well it worked out didn't it?" Mara said. "You two went way farther than I even could have hoped. There must have been lots of buried tension between you."

"So we're just as fucked up as you. Nothing to be proud of."

"Maybe not, but does this mean there's a chance of another threeway happening?"

Mara looked almost comically hopeful, like a kid on Christmas morning. My sister, however, was looking more thoughtful.

"You know what, the chances get better if you give us a little privacy right now," Zoey said.

"A lot better?"

"Just go."

Mara clearly didn't want to leave, but there was too much at stake for her to risk pissing off my sister and she knew it. A moment later I was once again alone with Zoey.

"Can't believe neither of us noticed her sneaking in," she said. "Bet you she's right outside listening at the door."

"Sorry, not taking that bet. I know her just well enough to believe she would," I said. "But, uh, I'm sorry about, you know, cumming inside you. I really didn't mean to."

"Not your fault," Zoey said. "You warned me."

"It's still kinda bad that it happened though."

"Yeah, it kind of is," she said, laying a hand just above her pussy for a second. "But there's pills I can take, it's not a big deal. I don't even think it's the right time of month for me to have to worry about it, but no point taking the risk, right?" She stretched out on the bed beside me, then rolled on her side facing me. "I know we might decide later that this was really stupid, and it probably was, but I don't regret it right now."

"Me either." I smiled and Zoey smiled back. "Were you serious about considering doing something with Mara again?"

"I dunno, maybe. Partly it was just to get rid of her, but I guess we don't need to worry about it being awkward for us anymore. Of course now I'm not sure about it for different reasons."

"Like what?"

"Like I'm not sure if I want to see you with someone else now."

"Zoey...."

"I know, that's kind of dumb. But I'm just really confused right now."

"Me too," I assured her. "We still need to work stuff out, we already knew that."

"But I don't want to get jealous of you. I'm not your girlfriend or anything, I'm still just your sister."

"My sister that I had sex with? What's that, like a sister with benefits?"

Zoey giggled, and after a second so did I.

"Something like that," she agreed. "But seriously, we need to decide what we're doing about Mara."

"Do we really need to that urgently? She's not going anywhere."

"Yeah, but think about it. She knows our secret and she could really help us keep it... or if we piss her off too bad by stalling...."

"You don't think she'd actually tell anyone do you?'

"Not really, but we already know she's willing to take matters into her own hands to get what she wants. Who knows what she'd do. All I'm saying is we need to be in control of the situation."

"Well, to be honest, I don't exactly mind the idea of sex with her, but I don't want to do anything that's gonna bother you. So I guess it's your call."

Zoey thought about it for a minute.

"Yeah, I guess I probably am okay with it," she said. "She's only interested if we're both there anyway, so it's not like I'll ever have to be jealous of you two sneaking off without me or anything. Just promise we'll have some time just for us without her though, alright?"

"Definitely. I assumed that went without saying."

"Good." She raised her voice loud enough it could be heard out in the hallway as she called to Mara. "Okay, get back in here!"

Not surprising either of us, Mara immediately opened the door and looked at us expectantly as she stepped back inside the room.

"So are we gonna do it?" she asked.

"Yes," Zoey said. "But not right now, so don't get too excited."

"Aw, no fair. I got all turned on watching you and now I get left hanging?"

Mara stuck her bottom lip out like a kid who didn't get their way, and even though I knew it was just to see if she could get to us, it actually kind of worked. She had a bizarrely sexy pout.

"Maybe Adam'll fuck you if you ask nicely," Zoey said. "It's up to him, but I'm done for now. I got chafed a little too much on his pants, probably should have just taken them off in hindsight."

Suddenly Mara's attention was all on me, and Zoey got up and moved to the other bed as though assuming my consent was a foregone conclusion. To be fair, it pretty much was. I would have turned down a chance at sex in a heartbeat if my sister was against it, but when she was the one suggesting it....

"Well... I guess if you watch it still kinda works," Mara said to Zoey. "How about it?" she said to me this time. "Not that I wouldn't do you anyway, but... you know how I am."

"Yeah, I know." I honestly hadn't bothered taking any offense to the idea that Mara wanted my sister present, it was the kind of thing I expected from her. "If you want to wait for me to recover, I guess I'm up for it."

"Oh I don't think it'll be that long," Mara said, a mischievous glint appearing in her eye.

With no warning she pulled her shirt smoothly over her head, then crawled onto the bed with me. My cock was still soft, not to mention covered in a mixture of mine and Zoey's juices, but she didn't seem to mind and eagerly started working on getting me hard again.

I exchanged glances with Zoey who offered me only a smile and a shrug, then I focused back on Mara who gave me a much more seductive smile. It was an odd sort of path that had taken me to a point where'd I'd get to fuck two girls in one evening, one of whom being my sister no less, but given the chance to do it all again, I doubted I'd change anything.