I grew-up in the same neighborhood as my aunt and uncle who had three daughters. The youngest was my age and the other two were quite a bit older. From my earliest memories I spent much of my time with the youngest cousin. We went to pre-school together, swim lessons, day-camps, etc.. and naturally took loads of baths together.
We were like best friends and really had no barriers between us. While naked in the tub we'd often talk about the difference between our parts-display them, examine them, talked about what they may be for, and even played some games. I remember her once saying, 'You've got a hot dog and I've got a bun!'
Sadly my aunt and uncle moved away. It was pretty devastating as I really had lost my best friend and confidant. But fortunately they were still close enough to get together once every Summer for a family camping trip, and an occasional Christmas or Thanksgiving. And every Summer we'd pick-up right were we left off the year before. We'd spend the entire week inseparable, swimming, hiking, catching frogs, etc.. It was great!
Then came the Summer after we had both turned 13. As always I was looking forward to seeing her again, but I didn't expect to see how much she was starting to change, even though I too was changing a bit myself. But we still picked-up right where we had left off from the year before without a hitch. Soon after we had our RVs all settled the two of us ran right out to hike the trails, visit the burned-down cabin, look for frogs, etc. But it was late so the first day was over far too soon.
The next day was our first full day and with plenty of sunshine we were both looking forward to swimming in the lake. Just a short walk from the campground was a nice beach with a diving platform floating maybe 50 meters off shore. From our earliest memories we'd both been good swimmers and would race out to the platform every day we were there. The platform had one very springy diving board, a high-dive board and a water slide. With this much fun available to us we'd spend most of the day at the lake out on the platform.
We all walked to the beach together and were wearing clothes over our swim suits. When we got to the beach she quickly took off the clothes covering her suit and challenged me to a race out to the platform. I must have looked pretty stupid as I stood there in awe of a beautiful blooming young women thinly veiled behind a modest one-piece black swim suit. But before I could take too much of it in she was already running to the water. I quickly lost my shirt and ran right after her.
On the platform we dove, slid, and dove some more, just like the fish we had always been. But naturally I was taking every opportunity to study the details of her new shape. And I really thought I was being sly about it.
One of our favorite tricks was to swim under the length of the platform. Years ago we also discovered that under the platform was a mesh of openings we could come up into and hide from everyone else. So naturally we soon found ourselves under the platform to hide, rest, and chat. As we came up I guess I wasn't too subtle about sneaking another peek at her modest cleavage. When my eyes came back up to meet her's she had a huge smile and just said, 'Yeah, can you believe it? I guess this means no more baths together, huh?' We both laughed, though I'm certain mine was far more nervous than her's.
'I'm sure you're changing too but you can hide it better!', then she dropped back under water and swam out from under the platform. The truth however is that I had more wood than I could hide under my suit.
I swam after her but stayed hanging on the edge of the platform until my wood went down while she took a couple more dives off the high-dive. She swam back over to me then said, 'I'm hungry. I'll race you back to the beach for lunch!', and took off with me over taking and getting to the beach just ahead of her.
We dried off, covered in towels and ate sandwiches we had packed that morning as we sat under the beach awning with our families.
After lunch she asked her mom for the keys to the RV saying she didn't want to use the beach bathroom because it's always so nasty. Her mom handed her the keys and sent her on her way, but then turned to me and said, 'Shroom, go walk with her please.' I did my best to look helpful and not excited at the request, got our RV keys and ran to catch-up with her.
At the campground we split to go to our respective RVs. When I was done I locked up and walked over to her door. I stood there for a bit then knocked.
I walked in, shut the door behind me, looked around but didn't see her.
'I'm still in here.', she said from the bathroom.
Then she opened the door and came walking out wrapped in a towel, which I assumed was covering her suit.
'I saw you looking at them all day. It's okay, I look at them all the time too! It's kinda freaky seeing how we're changing. Anyway, I thought maybe you'd like to have a real look at them.'
Then she slowly dropped the towel off of her shoulders to reveal the most perfect breasts I've ever seen before or since. She just stood there with the towel around her waist while I did my best not to drool while staring straight at them.
'huh.. oh, yeah, they're beautiful!'
'uh, thanks.. but well.. I thought since you get to see how I'm changing I should get to see you too. Doesn't your hot dog get bigger when you grow-up?'
If I wasn't hard enough before, with those words I nearly split my shorts. I fumbled with the string then finally got it loose enough to spring him free from his wet-suit prison.
I was looking at her face and could see she was intently staring right at my raging hard-on.
'Oh! Your hot dog is a lot bigger than I remember.'
With that I took a step forward then burst out a stream of cum right at her feet, followed by a few more spurts making quite a mess all over the floor.
'Wow! Was that because of me?'
'yes, I'm sorry.'
'Don't be. That was hot! Does it do that a lot?'
'Well, never on it's own like that.'
'I can make myself explode a little too if I play with my bun, but never that big of a mess.'
'You play with your bun too?'
'Well, yeah, sometimes. Just like you play with your hot dog I'm sure. But different of course. Want to help me'
So she sits down on the sofa-bench and asks me to sit next to her. She slightly parts her legs, just like I remember from our tub time years ago, then takes her fingers and parts her lips slightly.
'Oh yeah, she's really ready! Lick your finger and touch her like this.', as she starts to finger her clit. It is swollen enough to be peeking out of her hood and I can see she's so wet it's starting to leak out onto her leg and the sofa.
I lick a finger and move it down her way. She pulls her finger away and guides my finger right onto her clit. Then to my shock and thrill, holding my hand, she starts rubbing my fingers against her clit and moving her hips into my hand. This builds quickly until she lays back, arching her back and begins moaning loudly with her eyes rolling back into her head. I can see her nipples are very hard and my hand and the couch is very wet.
When she regains some composure she looks at me and smiles. Then looks down to see I'm just as hard as before.
'Wow.. That was way better than doing it alone! It looks like he still wants to play. How do you play with him.'
'Well, just with my hand too.'
'Can you show me?'
I take my wet right hand and rub it all over my rock hard tool.
'It's way better when it's wet.' I say.
'Well I've got plenty of that!' as she opens her legs a bit. So I take my hand and wipe up as much of her fluid as I can and cover my hard-on.
..then start slowly stroking him. And I can see she's staring straight at him.
'Is he going to make another mess?'
'Yeah, but maybe not quite as much.'
'damn.. we have a big enough mess to clean up already. I know, here..', she says as she gets down on her knees right in front of me.
'I know you like looking at these. Go ahead and shoot on them so we don't get any more on the floor.'
I had no objections and quickly stroked to a shuttering orgasm and a half-dozen thick blasts of cum all over her perfect breasts.
'Wow!', she says. 'That looked like more than the first time! We better clean this up in a hurry. How long have we been gone?'
So we both grab our towels and wiped up the mess on the floor, the couch and ourselves. We were joking and smiling at each other the whole time. We then quickly got dressed and stood there each holding our fluid soaked towels realizing we have to so something with these. So we hiked out to a lakeside trail, rinsed them off the best we could, then hung them up to dry in the campground. We grabbed fresh towels then walked quickly back to the beach smiling ear-to-ear.