Please make sure to read parts I-IV first. 

Part V

An hour or so later Kasey and I were still laying next to each other each just enjoying the contact with the other's naked body. Kasey rolled on to her side facing me and said, "Well, it's Thursday. Mom and Dad get back tomorrow evening. What do you want to do with our last night?"

"I'm not sure. Mitch will be back soon. I figure the three of us can come up with something to occupy our time," I replied with a smile.

"I've actually already got an idea," she said.

"Oh really? Do tell."

"Nope. It's going to be a surprise for you guys since you've been so good to me," she said.

"A surprise huh? No hints?" I asked.

"Nope, you're just going to have to wait," she said.

"Oh, is that a fact? Well, I guess I'll need to do something to take my mind of things," I said.

With that I playfully grabbed her and turned her on to her stomach tickling her while I did it.

"Hey! Stop that! That tickes! What are you doing?!" she laughed out.

With her on her stomach I got between her legs and shoved a pillow under her pelvis raising her hips up a little.

"Just occupying my time," I said.

Then I grabbed my now hard cock and, in one motion, drove all the way to the hilt in her still wet pussy. She let out a loud gasp as the pleasure of suddenly being filled with my raging manhood coursed through her. I dew myself almost completely out before thrusting hard back in.

"Oh god Pete. Oh, yeah. Fuck me. I need your hard cock inside me. Fuck me hard!" she yelled out.

Hearing that drove me mad. This wasn't sweet love making. This was pure animal lust. I stared down at my sisters voluptuously curved hips and ass as I drove my cock into her forcefully over and over. With each thrust her ass cheeks jiggled, just driving me even more wild. She kept making little whimpers of pleasure, and at some point she slipped her hand underneath and was furiously rubbing her clit as I pounded into her with everything I had.

"Oh Pete! Oh Pete! I'm gonna cum. It feels so good. Don't stop! I'M CUUUUUMMMMMIIIIINNNGGGG!!!" she yelled.

Her pussy clamped down on my cock like a vice. The shear ecstasy of that feeling combined with the knowledge that for the second time today I was fucking my beautiful sister drove me way over the edge. As she screamed out in pleasure I grunted as a volcano of hot cum erupted out of my cock filling her pussy yet again. As I finished cumming I collapsed next to her panting with exhaustion.

"I"…"think"… "that"… "will hold me"…"for a bit," I panted out.

"Ungh." was all she could reply.

After getting cleaned up once again. Kasey disappeared into her room, and Mitch finally returned from doing his chores at home.

"Damn man. That felt like it took forever. I hope I didn't miss out on too much action," he said.

"Maybe just a little," I replied with a grin.

"Oh really? What happened? Did she suck your cock again?" he asked.

"Not exactly," I replied.

I filled Mitch in on all the details of what happened.

"Holy shit! You really fucked your sister? I know you talked about it, but I wasn't sure you'd actually do it!" he said.

"Yep, and she was fantastic. It doesn't weird you out does it? I mean I know it's technically wrong I guess." I said.

"Hell no. Like I told you before man, if I had a sister like Kasey I would be fucking her everyday regardless of our relationship. She's fucking hot!" he said.

"Ok. Cool. By the way, she said she has a surprise for us tonight. She said she wanted to do something special on our last night before my folks get home as thanks for being so 'good to her'." I said.

"Really? Any idea what it is?" he asked.

"Nope, none" I replied.

"Damn man. I bet it's something really hot. After that story of yours and now thinking about her surprise I'm really fucking horny" he said.

"Want me to help you out with that," I asked.

"That would be awesome!" he said.

With that we went up to my room. When we got up there I shut the door and quickly got on my knees in front of Mitch. I slowly started rubbing the now fully formed bulge in his shorts.

"Hmm. You do need some help don't you?" I wryly asked.

"You have no idea man," he replied.

"Far be it from me to keep a friend waiting," I said.

I undid his belt and button, then lowered his zipper. I dropped his shorts and boxers at the same time letting his wonderfully large cock fall free. The tip was already glistening with precum. I grabbed the shaft with my right hand and leaned forward licking the head all around.

"Oh yeah," he gasped out.

I quickly got the head thoroughly wet with a mix of my saliva and his precum. As I stroked it with my hand each time I took more and more of him into my mouth. Eventually I slipped his head past my throat and had him all the way in.

"Oh god man. You're so good. Please don't stop." he said.

After sucking him all the way in and out a few times I slid his cock all the way out of my mouth. I continued to stroke him with my hand as I asked, "Now that you're good and excited, how about giving me a good fucking?"

"Hell yeah man. That'd be fucking awesome!" he said.

I reached into my nightstand and pulled out the KY. I stripped naked and rubbed a bit into my asshole and onto his cock. Then I climbed onto the bed on my hands and knees.

"You mind if this this time I do you like you did me the first time?" he asked.

"Not at all" I replied.

I rolled over onto my back and slid a pillow under my hips. He raised my legs up and put my calves on his shoulders while he lined his still raging cock up with asshole. Once he had the head lined up he just pushed forward. He slid in very smoothly this time, going all the way in. It felt amazing having his cock fill me up. I immediately became so intensely hard it almost hurt. He thrust into me with long slow strokes enjoying the sensation of my asshole gripping his cock tightly. With the warm up I gave him it didn't take long before he started speeding up. My body was tingling all over from the pleasure of him filling me so full. I hadn't even touched my cock, but I didn't think it would be long before I came again. Just as I could tell he was getting close he reached around my leg (still draped on his shoulders) and started furiously jacking me off. All of a sudden I felt his whole body go rigid and then he unloaded a massive load of hot cum into me. It felt incredible. I started cumming immediately with him coating my stomach and his hand.

"Damn man. I needed that," he said.

"Happy to oblige," I replied.

"I hope you guys aren't too worn out. I have a feeling you're going to need some energy tonight," Kasey said as she stuck her head in my room.

"Oh, I'm just getting started," Mitch replied.

For what felt like the third or fourth time today I went to get cleaned up. Mitch and I decided to take separate showers this time to keep from starting anything else. We wanted to make sure we had enough in us for Kasey's surprise.

While the three of us were eating dinner I was starting to wonder about this surprise.

"So, what's up Kasey? When do we get this surprise you keep talking about?" I asked.

"Yeah! What gives?" Mitch asked as well.

"Don't worry you guys. I haven't forgot. I have to run out and get it about 10. Keep your pants on." she said.

"Kasey. We'd have to be wearing pants to keep them on," I replied.

"Oh, fair enough, well just be patient," she said with a wink.

After dinner Kasey left for a while, and said she'd be back a little after 10 with our surprise. We were both so excited we could barely contain ourselves.

"What do you think it is man?" Mitch asked.

"I have no idea. You got any thoughts?" I replied.

"I dunno. I bet it's some kind of awesome sex toy that we can all use at once!" he said.

"That would be something. I guess we'll just have to wait and see," I said.

About 10:10 we heard Kasey come in the front door. We ran up to meet her.

"Ok you guys, I have your surprise, but you'll have to go upstairs and wait for me to call you down. I have to get it ready," she said.

We tore up the stairs. We could both hardly wait. The few hours of time off had really helped our young bodies. We were both sporting full erections without even having to touch ourselves. It didn't take long before Kasey called up to us, "Ok guys come on down."

We scurried down the stairs and ran to family room. Kasey was standing there completely naked, but that wasn't the surprise. Standing next to her was her friend Elizabeth, and all she had on was a red, satin bow tied around her waist. Now let me take a second to describe Elizabeth. Like Kasey she was 15 years old. While Kasey was curvy and voluptuous Elizabeth was smaller with just enough curve. She was only about 5'4''. She had shorter black hair that was styled so that the ends flared out in various places. Here eyes were a very dark brown, almost black as well. She had creamy white skin without a flaw to be found.  She had beautiful c cup breasts that were tipped in small dark purple nipples with aureolas the size of quarters. Her waist narrowed considerably then flared out into lovely hips. Her pussy was completely hairless. She did a little spin for us so we could see her beautiful heart shaped ass that sits up so high the way it only can in youth. She had wonderful, athletic legs with beautiful calves tapering down to meet dainty little feet. She was, in a word, gorgeous. Mitch and I were both speechless.

"Well guys, what do you think of your present?" Kasey asked.

We just stood there with our mouths wide open. They both seemed to appreciate this, and when we didn't reply Kasey turned to Elizabeth and pulled her close. Their lips met, and they kissed the way only two women can. It was soft and beautiful on both sides. Their hands roamed each other's bodies. Kasey slowly untied the bow around Elizabeth's waist as we watched with complete rapt attention. With the bow discarded Kasey helped Elizabeth to the floor and then leaned her back. The entire time they never broke their kiss. Once Elizabeth was fully laid back, Kasey slid down and took one of her nipples in her mouth. Elizabeth gasped in pleasure. Kasey continued to slide down, and eventually made her way between Elizabeth's legs.

Mitch said, "Holy shit man! She's about to.."

"I know." I followed up.

Then, Kasey used her tongue to lick Elizabeth's beautiful slit across it's full length. Elizabeth was obviously in a state of total ecstasy. Kasey looked like she had definitely had practice at this. Mitch and I moved closer so we could get a better viewing angle. Kasey continued to eat Elizabeth for all she was worth. She would switch from licking her clit and fingering her pussy to just using her tongue on the whole thing. Sometimes she would suck on her pussy. I couldn't believe what I was seeing. I was so hard, but I was so distracted that I didn't even think of touching myself. Mitch seemed to be in the same state as me. Eventually Elizabeth's chest started to flush and her breathing got very rapid. She bit down on her lower lip and her whole body locked up, then she screamed out as her body began to tremble. The orgasm ripped through her body with a ferocity I hadn't seen in any of the pornos I'd watched before. It was incredible. As Elizabeth came down from her orgasm Kasey lie down next to her.

"Well guys. I think you know Elizabeth." she said.

"Hey Pete, Hey Mitch" Elizabeth said with a blushing grin.

"Elizabeth, you have no idea how happy I am, we are, to see you," I said.

"Um, actually I think I can tell," she replied glancing at our raging erections.

Kasey followed up by saying, "So, I've told Elizabeth all about our time together here, and she was very excited to be a part of it. I thought it would be a great way to finish out the week by including her. She told her folks she's staying at a friends, so she'll be here all night. She is also, in very serious need of a good hard cock. So, the only question remaining is, who's going to be the first to give it to her.

"Hell Pete, as much I'd love to get first crack at her you set up this whole week, so I think you should" Mitch said.

"Awesome man. Thanks!" I replied.

I laid down on the floor between Elizabeths legs. Before I even tried to enter her I wanted her to feel good, not like I was just using her. I leaned down and kissed her on the lips. It was lightly at first, but we quickly started kissing more passionately. As the lust began to fill my body I reached down to line my painfully hard cock with her dripping wet pussy. As I did, she leaned up and whispered in my ear, "Please go slow and be careful. I'm still a virgin." Holy shit! The lust in me shot up exponentially. I was about to take a beautiful girls virginity for the second time in a day. It was all I could do to stop myself from just driving right into her. I controlled myself though. I wanted Elizabeth to enjoy this as much as possible. I kissed her deeply and pushed my head into her. It was a tight fit, but we both were enjoying it. I pushed in all the way to her hymen. Then I stopped, and just started thrusting in and out just up to her maidenhead. While I was thrusting and kissing her I slid my right hand down between us and started rubbing her clit. This drove her crazy. She started panting, and broke the kiss. It was obviously driving her close to an orgasm. I leaned down took her nipple in my mouth while she continued to build toward her orgasm. I could feel her body start to tense, and as the orgasm tore through her body I kissed her again passionately and drove my cock through her virginity. She yelped as I tore her innocence from her, but the pleasure of the orgasm quickly took over, and she kept shaking in ecstasy. She locked her legs around my back and squeezed me as tight as she could with her arms, legs and her pussy. This was more than I could handle. I yelled out as cum blasted out the end of my cock and filled her no-longer virgin pussy.

As we finished I rolled off Elizabeth and looked over across her body. Kasey was on her back with Mitch between her legs. She was obviously getting very close to an orgasm. She was meeting each of his long thrusts with her own. He was grunting with the effort. Her beautiful breasts would shake furiously with each thrust. I felt like I should be a little jealous, but I wasn't. I was happy that my best friend and my sister were enjoying themselves like this. Kasey went completely rigid as she had a tremendous orgasm. Mitch apparently wasn't quite ready yet as he just kept thrusting. As Kasey's orgasm subsided it looked like Mitch's was about to hit.

"I'm about to cum. Get ready." he yelled out.

"Quick, get up. I want you to do it on my face." she said.

Needless to say, I was a bit shocked. i didn't know where Kasey had gotten that idea. Mitch quickly jumped up and Kasey took his cock, still glistening with her juices, into her mouth. She furiously sucked and stroked it. As Mitch tensed up she pulled it out and aimed it at her face. Mitch grunted as pearly white cum shot out of his cock onto her face. Several shots landed across her cheeks and nose and eyes. A couple at the end dropped down onto her tits. Then she took his cock back into her mouth and finished sucking him clean.

All four of us lay there on the floor recuperating in a state of utter bliss.

"Oh my god. I can't believe how awesome that was." Elizabeth said.

"I told you. We've been having all kinds of fun." Kasey replied.

"What now?" Mitch asked.

"How about we take a quick break. I need a some water, then we make the most of this last night." I said.

"Sounds like a plan!" Kasey said.

After taking a bit to refresh ourselves and get a drink. The four of us met back in the living room. We pushed all the furniture aside and basically continued where we left off. That night is a night I will never, ever forget. The four of us basically fucked and sucked in every way our young minds could think of in basically every room in the house all night long. At some point I was fucking Kasey again as Mitch fucked Elizabeth. Later the two girls were locked together in a 69 as Mitch and I were locked in one of our own. At another point we were in a crazy sort of daisy chain circle each person with another person's cock or pussy in their mouth. Still later I was fucking Kasey from behind as she ate Elizabeth and Mitch fucked me in the ass. I lost track of how many times I came, and I can't imagine having that kind of stamina or recovery ability today, but it was incredible. Finally, with sunrise well past we all collapsed in a sweaty, sex-drenched pile exhausted.

"This, was singlehandedly, the best week I've ever had," I said.

"No kidding man. I had no idea anything could be this good" Mitch said.

"Thank you so much guys, for letting me join in" said Kasey.

"Yeah! Me too!" said Elizabeth.

"Are you kidding! It wouldn't have been nearly this awesome without you guys!" I replied.

After a bit of recovery time, Kasey and Elizabeth helped Mitch and I get the house cleaned up for my parents arrival. After they left Mitch and I plopped down on the couch and watched some TV. A little while later my folks got home.

"Hey guys. We're home" my mom said.

"Welcome back. How was the trip?" I asked.

"Oh it was great. We had a really great time. Looks like you guys kept the place pretty clean." she observed.

"We tried." I said.

"Well, I hope you guys enjoyed yourselves and having the house all to yourself while we were gone. What'd you guys do?" she asked.

"Oh nothing much. Just hung out, played some games, you know the usual." I said trying to hide my smirk.

If it's still well received I've got more to come. The next parts will not take place immediately after this though. There will be a bit of a time gap.