Never have I felt the emotion and feeling in a room change more quickly or drastically. What began as a fun and lighthearted moment among siblings had suddenly shifted into something much more significant and meaningful. After all that had happened my sister had kissed me again. I had expected that to never happen again. We withdrew from the kiss and locked eyes.My heart was pounding and I had a zillion thoughts racing through my head. I had no idea how to proceed next. Was this kiss purposeful? Was it just an old reflex? Was she about to freak out and run away crying? I had no idea and I had no fucking idea what to do. So I froze. I looked at Brittany, her beautiful hair slightly falling over her faced. She replaced the small lock to the spot behind her ear with her fingers.Then she leaned in and kissed me again. And again. And the next thing I knew our tongues were in each other's mouths and we were holding each other. I held her close to me, holding her tightly as if I was never going to let her go again. The kissing became more passionate. The only sound in the room was heavy breathing and the conversations being had on the movie droning on behind us.Luckily our family room is two flights of stairs down from our parents' bedroom so we would have plenty of warning if anyone came down. We were in our own world. Our own wonderful, beautiful world.My sister reached under me and removed my shirt, our kiss only breaking for the slightest second as it slid over my face. She had her hands behind my head as we continued kissing, our lips and tongues compensating each other in perfect unison. I'll always remember how good of kissers we were together. I've kissed plenty of other women since but no one has ever fit together with me as well as Britt did.Brittany rolled over and straddled me as we continued to kiss. I began to gain some of my old confidence, now obviously realizing that she wanted this and that THIS was going to happen. I grabbed her butt and ran my hands over her thighs. She leaned back and pulled her shirt off before leaning back down and getting right back down to business making out with me. I effortlessly reached up and unhooked her bra, letting it fall to the side.My sister was amazing. She had snapped back into shape after having Jack and was back to her pre-pregnancy weight. Of course, with the added bonus of adding a cup size to her wonderful breasts. I took them in my hands, giving her nipples a tug just the way she loved as she continued to kiss me.As we continued to make out, the rest of our clothes came off. She removed my pants first and gave me head. It was everything I could do not to cum as soon as her lips touched my dick. I returned the favor...removing her pants and having her spread her legs in the corner of the couch as I savored every delicious taste of her pussy.She came hard on my mouth, breathing heavily but taking care to stay very quiet as her orgasm subsided. She pulled me up to her, kissed me on the lips, then backed away and closed her eyes as she bit her lip; seemingly enjoying her own essence.She looked back at me and managed a, "Make love to me Sam...please."I had learned. "But um...I don't have a...I don't have a condom with me.""They put me on the birth control shot after I had Jack, Sam, we have nothing to worry about."I didn't have to be told twice. I moved forward, cradled my beautiful sister in my arms, and slid my cock all the way into her. We turned on the couch so that we could be in a comfortable missionary position. Very slowly I started going in and out of her, taking care to be gentle. We continued to kiss. The sex was so emotional and meant so much to us.I continued with very full thrusts but moving very slowly. She would open her eyes every so slightly to catch my eye contact and then close them and take a few hard breaths. We were both breathing hard by the time I came, just a couple minutes after we started. It was too much...the moment, the feelings, the absurd amount of turned on i was by this beautiful woman. I came deep inside of her, pumping several more times as I emptied.Now usually I'm a guy that needs at least a little rest in between "goes." To this day I always need 15 minutes to half hour usually. But not that night. This could be a last time of my life kind of experience and I wasn't going to let it slip by. I got up on my legs and turned Brittany to the side. I entered her again in sort of a sideways position where her legs were both lying to one side and I was sitting up.She felt tighter this way but also extra lubricated from my cum. I began to pump into her again, being a bit more strong and forceful this time, fucking her hard. We continued on in this position for some time, Brittany letting out a few small moans and grabbing the pillow and biting it as she came. She then turned all the way over and had me fuck her doggy style. Oh my gosh her ass. It was even more round and tight than I remembered. Just the site...the memory now even...was enough to send me to the edge.There was a mirror against the wall in our family room and I remember being able to see us in it while we had sex doggy style. I remember the strange imagery...the two of us kids doing what we were doing, knowing it was so wrong. But in the mirror we just looked like two adult lovers. It looked like a porno. it turned me on to see us that way and I absolutely loved it. It felt like we were grownups, lovers that couldn't stay apart and had to do what we had to do.After she came again she got me to lay at the end of the chaise lounger and rode me. She looked so beautiful. And she was SO. GOOD. She rode me fast and hard until I came again. Her naked body collapsed onto me and our heavy breathing slowly but surely subsided. She stayed on top of me for a long time.After some time I thought she might be sleeping. I was lying there just thinking how happy I was. This beautiful naked woman is lying on top of me...not only is she beautiful and naked but she's my sister and my best friend in the world. Things have been difficult as hell but we were happy. We were happier than anyone in the world at this very moment."I love you Sam," Brittany said softly, breaking the silence."Ha, i thought you were sleeping babe...But I...I love you too," I replied."I know we've been through a lot...things have been crazy. But I'll always love you. You're everything to me. You're my best friend, the love of my life, just...the best brother in the world. You mean more to me than anyone, okay?" Britt said."You too Brittany....I'm sorry for everything..."My words hung on in silence. She snuggled into my chest and I held her tightly. After some time Jack began crying for his overnight feeding. Brit woke up and got dressed and went to grab him upstairs. I dressed and went to bed. We enjoyed Christmas as a family the next day, the best Christmas I've ever had. Britt and I were back to normal, feeling good about things. We were joking with each other, smiling at each other, feeling in love.The next weekend we got together as was our new tradition. I wasn't sure what to expect that day and had butterflies. It was like going on a first date but with my sister. I wasn't sure if she had been thrilled about what happened on Christmas or regretted it, whether she wanted to continue things this way or what.We hung out and had a great time with little Jack like always. We talked, we watched movies, and cracked jokes. When Jack went to bed we found ourselves cuddled with each other on the couch. I wasn't sure how to continue on but I knew that I wanted to end up in Brittany's bed at all costs.I pulled her a bit closer to me, kind of spooning her while we watched an episode of (insert early 2000s sitcom here, I don't remember haha). I decided that I'd be bold unlike so many other times and rolled toward her and started to kiss her.She kissed me back momentarily and then pulled away a bit uncomfortably."Listen," Britt said looking downward..."We need to talk about this...stuff."I was shocked and hurt. "What...what do you mean, like you don't want to do it anymore? I thought we were past all the stuff that happened?" I replied somewhat angrily. Looking back, I was such an immature dick. I never understood stuff back then and feel like such a heel when I think about it now.Britt went on to explain. She was in love with me. Head over heels. She was in love with me since the first time we kissed each other. She was in love with me while she was with Mike, she was in love with me while she was pregnant, and was in love with me while she wasn't speaking to me.I expressed that I definitely felt the same way. I wanted to be with her . We were perfect together! And we had a son together! And our chemistry...off the fucking charts!!He next words I remember verbatim, word for word and can still hear them echo in my brain."This...relationship, while it's so good and so perfect, Sam. It...it just can't happen. Think of all the pain and tears it's already caused. For me. For mom and dad. For you. We'll never escape the secret of all this, no matter what we do. It'll always catch up to us and make us feel that way. Do you want us to be a couple who can never let anyone know how much we love each other?"I didn't know how to answer. I wanted to ride in on my proverbial white horse, tell her I loved her and would forever, and that I'd do whatever it took for us to be together. But as always, Brittany was the leader...she was the big sister and knew what to say and what to do."I want to keep doing this, I do...believe me I do Sam. But we're going to be alive in 20 years...in 30 years...heck, 50 years! We can't live with this secret for the rest of our lives we just can't. We'd be happy together but never happy in life. Not like this. Not with the pain and secrets and lies. We both deserve to be happy right?""Yea, I guess so..." I muttered."We need to live our lives. We have these memories, we have Jack. This whole thing was fun and I loved it. And I know you loved it. And we're beset friends of course! And soulmates even! But we both deserve a life...a fun, fulfilling, happy life. And it can't happen if we're together."I remember thinking, "Holy shit she's breaking up with me...that's what that feels like." We continued talking for hours. Talking about our fun times, our awkward times, our fun times. I asked for one last real kiss, which she gave me. We laughed about all of our good times and swore that we would remain best friends but nothing more. I understood what she was saying about our lives. I didn't like it at all but I respected and understood it.She hugged me when I left late that night and I went to my car and cried. Unsightly for a guy my age to be breaking down and bawling in his care in the middle of the street but that's what I did and I'm not ashamed to admit it.My sister and I never had sex again. We had a couple weak moments that first year or so where we kissed each other but she stopped things before they caromed out of control. Then things got easier. Life happened and we both got busy. We dated other people, got involved with other things, and while we continued to be close friends we grew apart as childhood friends/boyfriends/girlfriends are wont to do.We both have families of our own now, of course Jack is part of both though he may not know it. We never talk about the fact that we used to be lovers and of course have never told anyone else about it. Occasionally we'll be sitting around at the holidays and talk about stuff we used to "get into" when we were young. My mind always shoots right back to those days, those couple of wonder years where we were lovers. I always wonder if hers does too...So in the end, I lost a friend. I lost a lover. I lost the perfect girlfriend. But I gained something else. I gained a soul mate and I gained the feeling of what really being ridiculously, goofily lost and totally in love with someone feels like. Many people don't get that. My sister will always be my first love and I'll always have those memories of ours together. Brittany, I love you and I always will. Thank you for giving me the best teen years anyone could ever ask for.