Keeping Our 18th Birthday Promise

She didn't even flinch, just sucked it right in when it came back down. Gently locking her teeth behind it's head her tongue started running circles. Oh, my, goodness! I wanted to take all she would give but knew my present state couldn't take any more without exploding and I wanted that first explosion to be deep, deep in her pussy.

I pulled out, stepped back to recover just a bit, and stepped around behind.

Her Behind!! Her glorious behind. As I stood there looking down on it with my swollen shaft aimed right at it's depths I could imagine nothing more wonderful than what I was about to do with it.

This is where cold, cruel, reality showed up. Darn reality anyway. Was I too close, too far, too high, too low? Where exactly was her opening in that enticing darkness?

I won't ever laugh again at young stallions who seem to hit everything but the target their first time or so. Bob and Sue made it look so easy. Just up and in then again and again. I began to realize it had not been their first rodeo.

I must have taken a bit too long. Sis started making Mmmm... sounds mixed with a bit of whining as she switched her behind with impatience.

I went with the easiest path and took her hips in my hands. I'd wanted to see what they felt like anyhow and it stilled her for a moment.

"Well here goes," I thought. Lined up with her crack I shoved forward to finally enter her warm, willing pussy, and slid down the slickness of her slit to put the tip of my shaft somewhere near her belly button.

We both laughed and I tried again, only to slide straight up and out the top with my tip near my belly button on the next two tries. When the next attempt somehow slid clean off to the left and down her thigh neither of us was laughing.

"Just a second honey I think I've got it now." Sis was trying to thrust back in frustration. I leaned slowly forward till I felt what had to be her opening bump gently into my tip a couple of times.

At last there it was. She must have felt it too because as I threw all I had into a desperate lunge forward she shoved hard backward.

Paradise!! Sis shouted loudly. "Oh Yes! We did it."

I was speechless with the wonder of having her wrapped all around me. Mr. cucumber had done his job well. I had all the room in the world to maneuver in there and set to work using it.

In no time at all I was slapping loudly into her backside trying to make each stroke full and deep. In less than a minute we both climaxed with a ringing shout on sis's part that started the chickens squawking in their coop. I just held her tight against me as I felt pulse after pulse gush from me into her.

She must have felt it too because she gave a long shuddering sigh. "Oh honey, there it is. That's what I've been wanting."

A moment later she stood and I slipped limply out of paradise. She turned to plaster those fantastic tits and the rest of herself to me as I lowered my face to give her our first lover's kiss.

When we finally came up for air I looked down at her in wonder. "Oh sis I can't believe we just did something that magical."

"Me either", she echoed.

"Right now though what I really want is to do it again and again as often as we can," I said.

"Oh heck yes!" she exclaimed.

"I'm just sorry we left our phones in the house," I observed.

"Why?"

"Because even if we didn't get the first time on video as much as I'd sure like to get the next one I don't want to leave this magical spot for a moment to deal with it."

It was then we heard a soft cough at the corral gate.

It was mom. "It's okay dear dad got it all on his."

Sure enough there stood mom and dad. Naked and grinning.

Busted!! We were so busted was all I could think. I was so shocked that their being naked and grinning didn't even register.

I was suddenly a teenager again in full defense excuse making mode. I guess it's a reflex.

"We've been planning this since we were eighteen. We just couldn't not do it. We made a promise then and tonight we've kept it," I blurted.

Sis was speechless, dad just grinned bigger. "Son it might not be what your mother and I may have planned for you two but what we just saw was an absolutely beautiful expression of love. You two were amazing."

Then it hit me. Mom was naked! Right in front of me. And she looked really hot! An older brown haired version of sis and smoking hot. Just looking at her I felt an erection rapidly building.

It had been my recognition that it was my mom naked that set me off almost instantly. I had built a big boner for my mother, right in front of her!

"Mom!, You're naked!"

"Ah the resilience of youth," said dad seeing my shaft now engorged to match his own erection.

My gaze however had locked with my mother. As I felt myself go up in a flaming blush her eyes went big and round, fixed on my erection. "Oh my!" she said.

Dad took mercy and broke the moment. "Okay son let's go get another couple of hay bales."

I turned to follow him. On the way to the barn I reflected that maybe I could appreciate now some of what they'd mentioned years ago about living briefly in communes in the early 70's. Apparently my folks had unappreciated depths. They seemed such conservative farmer types most of the time.

While we were in the barn about to pick up a couple of bales dad said, "Hold up just a moment son. We need to talk a bit about what just happened when you saw your mom out there."

"Oh no." I thought. "Dad there was just nothing I could do about it. I mean gosh all it took was one look. There was just nothing I could do. She's just, well, beautiful dad."

"It's okay son, you didn't see anything I haven't seen for years every time I look at her. You're absolutely right. Trouble is she just doesn't believe she's really beautiful or exciting."

"What? That's ridiculous."

"Well I know that and you know that. In fact if she weren't your mom and you had had her bent over in front of you instead of your sister you'd have mounted her in a heartbeat too wouldn't you?"

I was shocked but before I could start denying anything dad held up his finger to halt me. "Don't deny it son, tell the truth."

That pause was all it took. He had me dead to rights. I'd have done my level best to screw her brains out. I just nodded in agreement.

"I've been trying all sorts of things to convince her. The latest I've got her started on as a dare is a little out there but may actually be beginning to work. What I need you to do when we go back out there is tell her what you just told me and then follow my lead. Okay?"

"Sure dad," I agreed with a big gulp.

Dad placed his bale a few feet away as a rest for his phone camera. Mom motioned me to put my bale right alongside the one sis and I had just used so well. She spread the blanket to cover both bales.

"Before we get started dear your son has something he needs to tell you," dad stated with a look at mom.

"About what happened a while ago when I saw you naked mom. That wasn't me still thinking of sis. That really was my natural reaction to how beautiful and exciting it is to see you naked." My erection built even more as I spoke to her.

Her eyes got big and round again. She opened her mouth to say something but before she could dad said, "Go ahead son and tell her all of it."

Looking right into her eyes I made a clean breast of it all. "Mom, if I had found you out here tonight bent over that bale like sis was the truth is I'd have done my very best to mount you and screw your brains out. You are so beautiful and exciting I can't help what you see happening right now." At this point my erection was full on stiff.

"Oh dear," was all mom said.

Dad chimed in. "That's right dear. He sees in you all the things all those folks who saw your naked pictures online emailed about completely voluntarily and with no moderating. It's not my imagination, you are objectively, demonstrably, beautiful and exciting."

"I'm beginning to see your point dear. My goodness it's still hard to believe, but I'll try."

Sis and I were just looking at one another with blank stares. Mom? Naked online? Really? Where? How?

Seeing our confusion dad picked up his phone. "Let me clear this up kids." He poked about on it for a bit. "A few months ago we ran across a truth or dare site that posts amateur nude pictures. The feedback, if any, is just whoever emails you. It was interesting."

"Then your mom told me they'd never post pictures of dumpy her. Her words not mine."

"Of course I told her they sure would and if we got enough email she'd have to let me get more to post on vacation. Well a month ago your mom finally agreed to the dare. No big surprise, her mailbox blew up."

"Dozens of folks saying how good she looked and not a single negative remark, right dear?"

Mom just nodded shyly and blushed a bit.

"Here, take a look," dad said and handed the phone to sis and me. Wow!! There she was. Our mom under a pseudonym of Deaux looking good.

"Way to go mom!" said sis as I nodded in agreement.

"Anyhow we've got something else to attend to now. You two can check the truth or dare pictures site out on your own time," said dad.

He led mom over to her hay bale and I took sis to hers. She and sis bent over facing one another.

Dad walked behind mom and I walked behind sis vowing I was going to make it last long enough to let us both better savor the wonder this time.

With just a bit of cautious alignment I slid right in this time. Sis was ready to go! So away we went.

Watching the rise and fall of sis's hips and the back of her head was thrilling. Seeing my mother's face and hips doing the same thing right in front of me was a whole next layer of excitement on top of the thrill of servicing my hot, juicy sister right in front of her mother.

Watching dad do to mom what his son was doing to his daughter right in front of his children was plain unreal. I felt myself seem to swell even more inside the heat, of my slick, wet sister. She must have felt something too. She began to buck and writhe, wanting me to fill her again with my seed.

I was helpless. I was going to cum any second and so was sis. Looking again at dad I saw him nod and just start slapping into mom's behind. I let myself go and did the same. The girls screamed and went limp almost as one.

I looked up again from where I still had a firm grip on my sisters hips. As I pumped her as full as I could I saw dad grinning back at me and doing exactly the same thing to mom. Talk about a father son bonding moment!

"Group hug," said mom as the girls stood up. The idea made sense at the moment but where was a boy supposed to put his hands on his stark naked mother? Dad came to the rescue. He put my right hand firmly down good and low on mom's butt right over her crack and squeezed so I had a handful of each cheek. He got her breast.

It was the absolute best group hug I'd ever had. After a moment dad said, "I'm thirsty. Let's get some lemonade." Arm in arm in arm in arm we went to the kitchen.

On the way there dad casually volunteered, "Oh yes, since we have all the folks here tonight to do it your mom and I have got a very special present for the two of you inspired by her favorite poster on that site."

"Oh my dear. Really?",asked mom.

"Yes dear, given he's your favorite you have to don't you think?"

Mom just nodded.

Cold lemonade was great. While mom and dad headed upstairs for a bathroom break sis and I broke out a laptop, googled truth or dare pictures and there it was. We gave the site a good fast look, taking the time to read what mom had put into her two posts to date. There we found her favorite, Stag Spice. Wow, inspirational stuff indeed. Mom must have a fairly wild secret side.

Hearing doors close we shut it down to see what dad had in mind to finish off the evening. We followed him back to the corral. He took off the blanket, stacked the hay bales one on top of the other, put the blanket on top and turned to mom.

"All right dear, you first."

Mom went to lie down face up along the stack with her arms hanging down and her bottom just hanging off the end. Her legs were spread wide just touching the ground.

As soon as she did that sis and I looked wide eyed at one another. Surely it couldn't be what we'd just seen on line? But as dad beckoned sis over we knew it was.

Oh! My! Goodness!

Dad had sis walk right between mom's legs, bend over her to place her head between mom's chin and boobs and spread her legs.

"All right son. I can see from your face you found this on line already so, Happy Birthday! Step right up. I'll expect my turn when we get back from vacation."

When I stepped up it was to find two well exposed, closely stacked pussies facing me. Wow!

I was about to become an actual mother fucker and somehow that was going to be just fine.

I took the easiest target first and slid right into mom. All the way. "Oh!", she said in surprise.

It dawned on me neither girl could tell when she was going to be penetrated. Cool. I gave mom a few strokes and started alternating. When I was in sis I tried to make sure the strokes were hard enough to make my balls slap into mom's opening.

In no time at all sis was sucking mom's tits and mom was stroking the sides of sis's boobs while they both moaned in concert with my efforts.

Mom climaxed first with a nice full throat scream. Sis came a dozen hard strokes later and set the chickens to squawking again. I came at that point, inside, outside, and all over both of them in a spectacularly slippery mess of a finish.

I spent a moment slumped over sis while running my hands over both of them.

"Got it!" said dad waving his camera triumphantly.

We all got back to the kitchen though three of us were a little weak in the knees for the first bit of the trip.

Our folks went upstairs to bed and sis and I did something else we'd never done. We took the nice, cozy twin bed in the guest room.

We managed to get through a shared shower without any more sex. I was still deflated. We did get some sleep but not as much as we might have. We simply made slow, steady love every hour or two till dawn.

At some point in the wee hours I asked sis, "Hey honey?"

"Uh huh."

"I'm keeping you full, any real chance you might get pregnant from all this tonight?"

"Uh huh."

I waited a bit. "Is 'Uh huh' all you've got to say?"

"Uh huh." Then she giggled quietly so I poked her gently in the ribs.

With a small squeal she said, "There's a fair chance. I've been ovulating today after all."

That caused a thrill of excitement to run through me but all I said was, "That's fine sis that's just fine."

And it was and still is.