Everyone in this story is 18 years of age or older. Minor and identifiable details modified or omitted to protect privacy. Dialogue reconstructed from memory.

Previous chapters:

• Prologue: A Relationship Opens

Part 1: A Big Discovery

Lindsey and I returned to campus for our junior year in an open relationship and news spread quickly. For the last two years we could barely keep our hands off each other. Everyone knew us as a couple that was - in a phrase - hot and horny. The reaction from our friends can almost universally be described as: surprised, but not surprised.

We had just spent the last few months discussing and sharing how excited we were to sleep with other people, so naturally we kicked off the school year by having incredible sex with each other. Two years ago we were cuddling and making love sweet and slow, nervously and excitedly exploring sex for the first time together, blushing and giggling when we made too much noise. As we made love for our second anniversary it was familiarity mixed with new urgency and passion. The love and attraction was still there and stronger than ever, but there was this sense that everything was about to change. We kissed deeply, passionately, my hands explored her curves as if I was tying to commit them to memory. We made love and fucked. As Lindsey rode my cock I sat up, holding her close, kissing her lips and neck, telling her how much I loved her. I felt her body tense and then she moaned that she was cumming, a second later I came as well, my cock pulsing inside of her. And as we sat there in the bliss of post-orgasm, the emotion of the moment overcame us and we began to weep in each other's arms.

It would have been the perfect moment to call this off, laugh about our silly idea, and live happily ever after, but perhaps we knew if we did that we'd look back and always wonder what could have been. Or perhaps we were just two horny 20-year-olds greedy for as much sex as we could get. As the night ended we lay intertwined catching our breath still uncertain about the future, but we finally didn't have the energy to dwell on it.

In the coming days the sense of excitement and adventure for this next stage in our journey returned. Lindsey and I called each other every day, teasing one another asking if we had gotten laid yet. We wouldn't have to wait much longer.

A few weeks later I joined some friends at a house party just off campus, and that's where I ran into Jo. She was leaning against a wall out of the way in a crowded, rowdy room holding a red Solo cup and looking a little out of place. This wasn't her crowd, nor was it mine. Jo is 5'7" tall, she has long pretty face, amazing slim fit body, flat stomach, C cup breasts, long brown hair with a single streak dyed blue, and a small but very cute round butt. Jo always dressed college casual: tank top, jeans, and a zip-up university hoodie she wore open in the front. Jo was quiet and shy, the kind of girl you'd be likely to find reading a book in the park, doing yoga in the gym, or curled up on the couch under a pile of blankets watching Star Trek. She was part modern-day hippie, part sexy librarian, and part hot nerd. I'd be lying if I said I hadn't thought about her before.

Jo was a friend of a friend. We weren't close, but saw each other fairly often at social functions. We met for the first time about a year and a half prior, and there was instant, mutual attraction. The sexual tension grew every time we saw one another. As I was in a relationship I was very actively, intentionally trying not to flirt with Jo or say or do anything suggestive while still being friendly with her. Jo too was clearly restraining herself, but by trying so hard not to flirt our actions unconsciously broadcast our feelings, albeit awkwardly. Imagine for a moment two attractive people who always seem to find a brief moment alone in a big group, each with a big dumb smile on their face when they see one another, aggressively maintaining eye contact, and showing a little too much interest in boring small talk, their conversation always ending with a long pause as they stare at one another sharing a silent understanding, then each abruptly finding an excuse to extract themselves right at the moment that something might happen that they'd regret.

Now, we were liberated from the tyranny of monogamy to act on and explore this attraction, but even with that freedom our dance was no more artful than before. In my excitement at seeing Jo I pushed my way through the crowd, only realizing when I was standing right in front of her I had no idea what to say. I wish that I could tell you that months of knowing I'd be in an open relationship had given me time to prepare a suave pick-up line to sweep my long-time infatuation off her feet the first time I saw her. In reality, I grinned like an idiot, stumbled over my words, and nervously made a dumb joke in a clumsy attempt to be charming. For her part, Jo was no more articulate than me. Upon seeing me approach Jo smiled ear-to-ear, her face flushed red, and she burst out laughing at my dumb joke as if it was the funniest thing she ever heard. She quickly said a few words in reply before shyly hiding her face behind her cup. I found her irresistibly cute.

Then, as if transported we were in my room, all over each other, her mouth on mine, our hands on each other's bodies, clothes falling to the floor around us even before we closed the door. Years of sexual tension finally had an outlet. We weren't thinking anymore, we had surrendered to instinct.

"I've wanted to do this for so long," she told me over and over as we sloppily made out. Jo sat me down on the edge of the bed, getting on her knees before me, resting her arms on my thighs as she pulled out my stiff cock. I'll never forget what happened next. A big smile quickly formed on her face, lust in her eyes, her shy demeanor melting away at the sight of my cock. "Oh my god! I kneeeew you were big! Lindsey is soooo lucky."

It's at this point in the story that I should disclose an important detail, something that plays a major part in things to come. At the time that I was exclusive with Lindsey neither she nor I knew... I kind of... have a big cock. If you want measurements (which I suspect some of you do), I am about 7 inches (or about 17.5 cm) long and exactly 6 inches (15.25 cm) around. Before this moment I hadn't really thought about how I compare to other guys, but thanks to my open relationship I would quickly learn and it will become a frequent theme of many of my future sexual encounters.

It wouldn't quite be accurate to describe what happened next as a blowjob. Jo briefly sucked on the tip of my cock to get it wet, but from there she stroked and gawked as she enthusiastically worshiped my size. At first I was stunned, asking incredulously, "really?!" Jo laughed, as if she couldn't believe I didn't know. "Ummm... yeah. You have a beautiful dick. It's thick. It's... really thick. You're soooo much bigger than every other guy I've fucked at this school. My first boyfriend was as big as you, and he ruined me for other guys. A cock this big hurts a little, but it hurts so good. You have no idea how bad I've needed to be fucked by a cock like yours again. You're going to have to get me warmed up to take this."

I pulled Jo onto the bed as I stood up. She was now laying on her back where I had been, legs spread, her cute butt right on the edge. I knelt in front of her and peeled her black g-string panties off to see her gorgeous thick pussy lips glistening with excitement, a trimmed mound of hair just above them, freshly shaved around. Jo began moaning the second my lips touched hers. She tasted so good. Jo rolled her hips forward pressing her beautiful sex into my face. I responded by grabbing her hips and pushing my face forward even more as I devoured her. "Oh my god! You can eat pussy and you have a big cock?! Yes, yes, yeeeesssss." Jo came hard, moaning as her hips thrust against my face. It was part pussy eating, part face fucking, and we both fucking loved what was happening. I slowed down for a moment before continuing to lick her this time pinning her hips down with my arms so I was completely in control. One armed draped over her midsection holding her in place, the other moving up her lean body to her breasts. I was starting to get a sense of her wants and needs, and I could tell the tension was building within her again.

"Oh fuck... I need your cock... please... please fuck me right now..." And she would get no argument from me. I stood up, spun her around and pulled her hips back so I could take her from behind. I slid on a condom as quickly as I could and mounted her. I held her hips in place as I teased her pussy with the tip of my cock. "Oh fuck. Be gentle it's been so long since I've had a big cock." I was losing my mind in love with her dirty talk. I got control of myself then slowly, gently thrust my cock into her tight wet pussy. Jo moaned and gripped the sheets as I penetrated her. I took my time and when I finally filled her with every inch I held it there so she could feel my full size. In that moment that I filled Jo I had another revelation: the perfect pussy exists and I had found it. The tip of my cock perfectly pressed against the back of her - it felt as though a millimeter more would have been too much for her to handle and a millimeter less wouldn't have felt like such a flawless fit. Her pussy enveloped my shaft so perfectly tight, all the way down to the base where I could feel her thick lips gripping and gushing juices all over me. I'm not exaggerating when I say it felt like my cock and her pussy were made for one another.

Jo came almost the instant I filled her. Within seconds she whimpered, moaned, and then the top half of her body collapsed into the mattress, her hips bucking against me as I strained to hold her in place against my body. My bed muffled her cries of pleasure. I had never even imagined that a woman could cum so easily. It was intoxicatingly powerful. My cock felt huge, and just as Jo began to recover we started to really fuck.

"Oh my god I love your big cock. I love that you're so thick. I feel so full. I've wanted this for so long. Yes fuck me, fuck me. Yes, yes, yes I needed this so bad. Yes... oh... my... gooooo..." Within minutes of her first orgasm Jo came again. This time I let her collapse onto the bed completely, then flipped her around. She was like a rag doll in my hands, her mind spinning as I spread her legs and sunk my hard cock into her once more, this time she was so wet and warmed up I penetrated her to the hilt with ease. We kissed and whispered dirty things in each others ears as Jo came almost nonstop - more than I ever thought was possible. It was so hot and novel I didn't last as long I usually do, but I think if I had lasted any longer Jo would have tapped out. She seemed to reach her limit in the time we had. When we finished she lay there breathing hard and managing only "you've got a great dick," before she passing out in my bed. I lay there trying to recall how many times Jo came, but I had lost count. At some point one orgasm seemed to roll right into the next. I had never experienced anything like it. Lindsey and I would regularly have great sex for twice as long with her reaching orgasm almost always once, sometimes twice, and on rare occasions more, but it was never like this.

The next morning we showered together, warm water washed over us as we made out, my fingers gently circled her clit, her slim body falling into me as she came one last time. She was too sore from the previous night to have intercourse again, but we enthusiastically agreed that it wouldn't be the last time. After she left I jerked off, thinking about Jo's beautiful face and body and her perfect pussy, but also about everything she said about the size of my cock. I felt so big and powerful I came hard as Jo's words "big" and "thick" echoed in my head. Then I made a big call.

Lindsey and I met for lunch, and it was uncomfortable. Even though we'd agreed to everything and talked about it for months it was a lot different now that we were here. It was no longer theory, it was our reality. Part of me felt ashamed like I had cheated. I looked down as I told her, unable to meet her eyes, only looking up when I finished delivering my news. Lindsey... wasn't thrilled, but wasn't mad either and had some direct questions that required direct responses. Totally fair.

Lindsey: "Who was it?"

Me: "Jo."

Lindsey: "Mary's friend?"

Me: "Yes."

Lindsey (unamused): "When did it happen?"

Me: "Last night."

Lindsey: "How did it happen?"

Me: "We ran into each other at a party. Went back to my place together."

Lindsey: "Did she stay over?"

Me: "Yes."

Lindsey (seriously): "Do you still want me to be your girlfriend?"

Me (emphatically): "Yes!"

Lindsey (mischievously): "Did you have fun?"

Me (nervously): "Um... well... I... yes."

Lindsey (nervously): "Is she... better at giving head than me?"

Me (laughing): "No. No she was not. She --"

Lindsey (hands up): "I don't need to know."

Both of us: (relieved laughter)

Lindsey (smiling devilishly, winking): "Good. I always want to be the best at that."

With the last statement the tension seemed to break. We talked about it some more and what it meant for our relationship. The conversation started rough, but by the end we were laughing and joking about it. I breathed a sigh of relief. Lindsey admitted she had been waiting for me to make the first move. She didn't feel comfortable sleeping with someone else first, and by sleeping with Jo I had in effect given her permission to fuck someone else. Looking back it occurs to me that if I hadn't fucked Jo then Lindsey and I probably would have called this experiment quits at some point and gone back to normal, but "normal" would now mean something very different for us. Now all I could do was wait until Lindsey fucked another guy.

While I waited, I did what any extremely horny 20-year-old would do: I masturbated... a lot, and a fascination with penis size was quickly becoming a big kink for me. I measured my cock for the first time in years that week, and not just once. I measured length and girth every day as I searched the internet for penis size stats, my erection raging as I remembered Jo telling me how I was bigger than all the other guys she had fucked in the last 2 years. That was a detail that I kept coming back to. I've spent years thinking about what this all meant to me and why those words and this kink took such a forceful hold of my psyche. The best way I can describe it is that it was the first time in my life I felt so powerfully masculine and sexual. Although I had guy friends, worked out at the gym, played sports, and did a lot of stereotypical "guy" stuff I had never felt totally comfortable in settings with a lot of testosterone. I hated locker room talk, never joined a fraternity, and all my activities in college were co-ed. While I had a core group of guys, I had an increasing number of female friends and found I was more comfortable in co-ed groups than with a boys night out. I was used to being seen as the cute, sensitive guy friend who was a good listener, and there was something so erotic about a beautiful woman seeing me as this powerful, raw, masculine sexual partner. Sex with Lindsey was beautiful and romantic, and although I knew she was attracted to me I still struggled at times to feel like I women would see me sexually. Learning that my manhood was bigger and thicker than most other guys was invigorating.

But there was another side to my new fixation on penis size. My girlfriend was now more determined than ever to fuck another guy, and now the looming question on my mind was how the size of my cock would compare to his. By the following weekend I got "the call." This time we did everything over the phone.

We were both a little nervous, but it was nothing like the first time. As she told it, on Friday night Lindsey headed to the nearest frat party wearing a tight black and white striped dress that showed off her huge tits and hugged her stunning voluptuous body. She wore makeup and lipstick, and her naturally blonde hair was freshly styled. Unlike me, Lindsey was always confident with her body, and her confidence made her even sexier. Lindsey had the body, poise, and sexuality of Angela White, and she wasn't going home without getting some dick. I wasn't there to witness it, but I'm certain she walked into that frat house and fucking owned it. She spotted a beefy frat bro who was checking her out, so she walked right up to him, introduced herself, and ended up naked in his bed, a used condom on the floor and his cum on her chest. As she spoke there was still that one burning question on my mind, but I found I was a little too nervous and embarrassed to ask. Lindsey finally broke the silence.

Lindsey (laughing): "There's something else I never realized before."

Me (nervously): "What's that?"

Lindsey: "You have a BIG cock."

To be continued in Part 2