I told the girls to get out and handed them towels. Swim trunks started sliding off and a few more boners popped out as we walked to the locker. As I helped the girls dry off the dad across from us scanned their flawless female forms, dwelling on their little puffy vulvas and Rachel’s enlarged nipples. His penis was ¾ erect before he noticed and with a red face turned his back to us and finished dressing.

The girls slipped on their sun dresses. They were all slightly different styles of backless dresses with a bib of sorts to cover the front. Rachel’s was almost too small for her as it barely hid her blossoming tits. In fact, if you looked at her from the side or above you could see those little beauties perfectly.

I took them for ice cream before heading home. Before going in I reminded them about keeping their pussy’s covered as I had gotten flashed again in the car. We got our order and sat down. Rachel looked down at her chest, pulling at her dress. “Grandpa,” she whispered, distressed, “I think my tits are showing. Everybody’s looking at them…”

I looked down at her chest. “Well, your dress is a little small… and you have beautiful tits… You can’t really blame them!” I teased. “Graandpaa!” she whined. “I thought you were proud of your breasts, and you want to have huge breasts like your Mom.” “Yeah, that would be so cool..” obviously imagining herself with her Mom’s rack.

“Well, you’d better get used to having people staring at your boobs!” She looked back down at them thoughtfully and then put her shoulders back and pushed out her chest and smiled, eating her ice cream. This just caused her nipples to peek out the sides of her dress top and draw more attention.

We got home and I said, “You girls can do the dishes-without fighting- I’m tired so I’m going to go have a nap for about an hour. I want you to stay in the house. Rachel, you’re in charge. You can go to the rec’ room and play Nintendo or watch TV. If I’m not up in an hour come wake me and we’ll go for a swim. Abby, make sure you wipe your seat when you get up.”

She spread her legs and looked down at her sopping little vulva.

“Oh darn, I wish it would stop…”

“I’ll give you something after my nap to help you with that.” I promised.

I walked to my room as they chattered about wet vulva’s, pussies- or boys call them cunts- Roxy’s has hair on it-eww- I’ll wash you can dry…

I vaguely remember the sound of the TV before I crashed into my power-nap. I woke the sound of three whispering voices.

“Hi, Grandpa, it’s been an hour so we came to wake you up.” Rachel said matter-of-factly to my uncovered groin. Just then I realized my penis was in a full blown erection and they were all staring at it wide-eyed. “Oh, shoot.” I thought to myself. As naturists this is bound to happen. I just was hoping for later rather than sooner as I know there will be a million questions leading to “the sex talk”.

“What did you do to Hermie? He’s HUGE!!” exclaimed Sarah at the sight of her disfigured new friend.

“Is that what boys call a “boner”, Grandpa?” asked Rachel. She seemed to already have a grasp on some of this ‘sex stuff’ albeit probably hearsay from peers.

“Can I touch it?” asked Abby as she grabbed it- her fingers not quite wrapping around it. “Wow, it’s stiff and hot!”

“Oh my, sorry about that girls, I didn’t mean to…”

“How do you make it DO that, Grandpa?” Abby interrupted as she rubbed down, back up to the glans and gave it a squeeze.

“Don’t DO that, you’re hurting Hermie…” said Sarah

“Boys at school say they ‘pop boners’ all the time and they don’t know why.” Rachel said as she reached out to grab it, too. “I’ve just never seen a ‘real’ one. It’s sooo cool, Grandpa!”

“Well, I’m glad I could contribute to your education, Rachel.” I said sarcastically.

“Roxy says guys pop a boner when they look at a sexy girl…”

“You mean Hermie LIKES to get huge?” asked Sarah, looking confused.

“So- tell your little sisters about “boners” Rachel…” I suggested.

“Well, in sex ed class we learned about boy parts and girl parts. And girls start to make tiny eggs in their tummies. And boys start to make tiny little seeds called ‘sperms’. And when the sperm gets into the egg a baby starts to grow. And when it’s born it comes out the vagina.”

“But they never told us how the sperms got into the tummy where the egg is. So Roxy said that’s why boys get boners-so they can poke it into a girl’s vagina and put the sperms in her tummy!” By this time her sisters each had a hand between their legs fingering their vaginas while staring at my slowly softening, but still ‘huge’ hard-on.

“No way, Rachel, would THAT fit in my vagina!” said wide-eyed Abby, the indisputable expert on what will fit in a vagina!

“Well, that’s pretty close, Rachel.” I said. “And when you’re older your vagina gets bigger. THAT-” pointing to my penis “Will fit –er-I mean, when you get married your husband’s will fit into your vagina and it feels good.”

They stood there dumbfounded.

“So why do-did- you have a boner, Grandpa?” asked Abby, noticing the continued shrinkage.

“Well, your body needs oxygen that you breathe into your lungs and the oxygen goes into your blood to your body. When the penis needs extra oxygen it fills up with blood- like a balloon- and gets hard- like it has a bone in it. That’s how it got the slang term, ‘boner’. The proper term is “erection”.

“E-reck-shun” they repeated.

“But if you want to put your sperm in a girl’s tummy how do you make your wiener-I mean-penis into an ‘e-reck-shun’?”

“Well, Roxy’s right about that, too. Looking at a sexy girl can help cause an erection. Or smelling a sexy girl; or touching…” With that I sat up and scooped them all together in a big hug.

“….Or hugging three sexy girls!! –Oh, no! I’m getting an erection!” I teased.

They all screamed in mock panic and ran, giggling, from the room.

That incident seemed to be the turning point in our relationships. After that they seemed to be always staring at my cock- looking for signs of an erection. Or they would find games or create circumstances that would put themselves in contact; or just close proximity to my cock to cause an erection. It almost seemed like a competition… hmm, imagine that, three sisters competing. THAT’S never happened before…

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