He's tricked into sex by a "depressed" friend.
Shelly turned to Katy. "What do you think, babe? Is it too much to cut his balls off?"
Katy said, "A nice thought, but too gory. No, I want to embarrass this boy. In fact, I really want to teach him a lesson once and for all. I know he's been sneaking peaks at me whenever he visits. He's always been a little pervert. Haven't you, Tommy?"
My blood boiled at this. I wanted to shout back right then and there that I knew her incestuous little secret as well as the fact that I had also secretly fucked her and was the one who REALLY made her cum, not her minute-man brother! But I managed to bite my tongue. If there was ever going to be a chance of resuming my big plan, I had to keep this information contained for now. Until something really painful or weird happened, I was resolved to endure the girls' "torture."
"I know! I know!" Shelly suddenly blurted. "We're going to do this eye-for-an-eye. Tommy got to see us naked. Now we're seeing him naked. Tommy got to see us go pee, so..."
Katy grinned widely and took over. "Yes! Let's see how Tommy feels about peeing in front of women!" In her zeal, Katy had loosened her grip on her mammoth mounds, and I could now see a good 80 or 90% of her boobs, including at least one nipple.
"Awesome," said Shelly. She nodded toward me. "So, go for it, Tommy."
I looked at her. "Are you kidding?"
"No!" she scowled. "Start pissing!"
"Wait!" Katy said. "Tommy, step into the river here. Don't pee all over our towels."
"Oh, yeah," said Shelly.
In full humility I stepped forward, closer to the girls, and I was now standing roughly between them, only a few feet away, the water coming to the middle of my calves.
"Do it!" Shelly ordered.
I looked down. I was still fully hard, rendering the act of urination impossible. "I can't," I said, truthfully.
"You don't have to go?"
"No," I said, gesturing to my boner. "I can't do it like this."
Katy frowned, "Goddammit, why are you still hard when we're trying to humiliate you?"
Shelly crossed her arms again, not to cover herself (her small breasts and nipples were still quite visible), but to contemplate the situation. She cocked her hips slightly and stared at my pole again. Then she snapped her fingers.
"The fucker is getting OFF on this, Katy," she said. "Guy's can't pee when they're hard." She licked her lips, zeroing in on my cock. "And boy is this guy HARD."
"So what are we going to do?" Katy asked, with feigned innocence.
"The only thing for it," Shelly replied, "is to relieve some of the pressure."
"Good question." Shelly finally raised her eyes to meet mine. In that moment, I could feel a very certain impulse: Shelly was enjoying this too. She was getting as horny as me, and she was using this "torture" session as an excuse to have some very naughty fun.
Or, at least I hoped.
She took a step closer to me, close enough so that all I'd have to do is reach out and grab her around the waist if I wanted to. I could smell her hair. My mouth watered.
She looked me right in the eye. In a low, husky voice, she said, "Stroke it."
There was a pause. I was staring right back at Shelly and couldn't see Katy's expression. I knew she had heard but had remained quiet. Shelly said it again, a little more firmly.
But this time I held my ground. "No."
"You heard me."
"But we want you to pee."
"And I need to cum first."
"So make yourself cum!"
"Fine, you fucking pervert, I will make you cum!"
Shelly grabbed my cock.
I let out a gasp of mutual surprise and pleasure. In about one second Shelly was already furiously stroking me. It was clumsy stroking at first, because Shelly was still looking boldly into my eyes, not really concerned about her exact grip. Her look was intense. It was as if she was daring me to dare HER to keep going. So I gave her a look right back that said, I absolutely dare you, bitch!
Katy blurted, "Shelly, what the fuck!"
"The boy thinks he has some self-control," Shelly said, her eyes still on mine.