We engage in normal beach activities

We spend the next hour or so engaging in regular beach activities. We toss around a beach ball, we take a dip in the ocean, and we even build sandcastles. But through it all, I have a perpetual boner.

It's hard to explain what kept my boner going. It might've been the girls' bodies glistening with sweat as we passed the ball around in the sun. It might've been the sensual way they frolicked in the waters, splashing one another and swirling their hair around. It might've even been just our close proximity while we were building sandcastles, and the way they 'accidentally' kept brushing against my cock.

Needless to say, by the time we retreat back to our beach umbrella, my cock is not only still just as erect as before, but throbbing with carnal desire.

"Dude, you really don't know how to control yourself, huh?" Becky says, glancing down at my cock as we all sat around under our umbrella on our beach mat.

"C'mon Becks, I've already said it's a natural reaction," I tell her for the umpteenth time that day. "Dudes can't help it, you know!"

"You mean they can't help it when they're surrounded by pretty girls," Samantha teased, tossing me a water bottle.

"Haha, don't flatter yourself too much, why not," I said jokingly.

"But seriously though, maybe you want to go off somewhere and take care of it first?" Susan suggested, eyeing my cock without a shred of embarrassment.

"No no, i'm fine, really!" I say. The truth was that being naked in front of my clothed friends was really turning me on, and I could barely stand it.

Becky let out a loud laugh. "Hah! I highly doubt that, bro. I kept thinking you were about to blow your load all over our sandcastle just now!" From the corner of my eye I notice Samantha and Susan quickly stifle their giggles.

"What, you think I can't last long?" I challenge Becky. An opportunity for something naughty is appearing, and I am eager to hold onto it.

"Yeah, that's right," Becky says, moving herself closer to me on the mat. "I bet you're a quickshot. I bet you can't last 5 minutes with a girl."