Terry looked at Sarah and Jess and sighed, "...Alright, fine with me. I mean, we're getting a lot of hot action from you two outta this, right?" He was feeling his blood heating up just thinking about what Sarah was gonna give him for this. Maybe she'd let him well and truly fuck her, hard and deep...
Sarah leaned forward and watched, enrapt, as Terry and Duke began to approach one another.
"Dude..." Duke started, visibly blushing and looking unsure about this, "I'm...not gay, y'know...how are we gonna...?"
"Just...go with what feels right, Duke. I know I am." Terry looked at the girls as he and his friend stood there, both shirtless, both looking one another over.
Sarah shouted from the sidelines, "Come on you two! Show some love!"
Jess tried to offer Duke some help, saying, "Duke, just think like Terry's me, okay? I'll make your day if you do this for me, big guy!"
Duke decided with that that he was done being nervous and he'd just go and get it over with. Besides, what's the most that could happen? An awkward boner? He moved in quick and planted a hot, heavy kiss on Terry. Terry was for his part shocked when this happened and returned the kiss with interest, wrapping an arm around Duke's shoulder and hungrily returning the favor.
The girls were definitely enjoying the show, even more so when it heated up.
Terry groped at Duke's musculature, pinching at his nipples, cupping his ass and squeezing it tight, drawing a gasp and a moan from Duke, "Dude...you're...you're gonna make me..." Duke shivered, and then yelped when he felt Terry rub at his groin.
"...Ooh...yeah, man? What am I gonna make you do?" Terry was flush, unable to believe this felt so...so good. It was a forbidden sort of charm, and he wanted more. He needed more.
"...Do something so...so fucking gay..." Duke gasped out.
Terry didn't need to be told twice and as he kissed Duke again, he felt his friend's reservations erode fully, and Duke returned it in full, one hand going to Terry's crotch and pushing his pants down, taking Terry's cock - which was unsurprisingly large and erect - starting to rub and touch at it.
Terry groaned and let out breathless gasps, quaking on his feet with pleasure, and gave Duke the same courtesy, the younger of the two suddenly gripping on to Terry's shoulders. "We...we gotta..."
"Yeah..." The two of them pressed against one another, half looking like wrestling as the two tried to sort out who would fuck the other in the sheer heat of their arousal. Both were completely over the moon with how they were feeling, and neither could stop now if they wanted to. Which neither did. Their manhoods crashed together in multiple accidental frottages and the two became slick with sweat. What was to start as just a make out was turning, itself, into a show for the girlfriends.
Sarah and Jess watched totally enrapt, and Sarah was basically drooling by this point - she had not expected to see this outside of some very interesting pornography. She turned and looked at Jess, "...thought those two were straight..."
Even as Terry finally asserted himself, getting behind Duke, both of them looked at Sarah.
Terry lined up his cock, and lubed it up, but even still said, "We're...still set...to fuck after this, Sarah, right? I'm still straight!"
Duke was preparing himself for what was about to happen, which he never in a million years thought WOULD happen. But now, he couldn't help himself. It was too much. "Yeah...just...just cuz we're foolin' around with each other doesn't mean we're gay or anything..."
Jess remarked under her breath, "...So says the guy about to take Terry's dick up his ass."
She and Sarah watched as the final phase of their "entertainment" began, with Terry beginning to fuck Duke, the slimmer man gasping and cursing as the big, muscular Terry bit his lip to stop himself from getting too far with this too fast...but with how the two of them had fooled around and built themselves up, their lacking, regressed staminas resulted in only one possible outcome.
Duke was the one aware of what was coming, and tried to stop it. He looked over his shoulder at Terry, still pistoning away and enjoying himself on Duke. "Dude...you're gonna..."
Terry safe to say did not hear him. Terry had firmly lost himself in a sea of arousal and indulgence in something he had never thought he would ever feel or partake in. His muscles were covered by a sheen of sweat, and occasionally he'd lose his standing with a leg due to how shaky he was at present. "D...Dude...what?"
But it was this inexperience that resulted in an early emission;
"F-Fuck! T-Terry...gonna...I'm gonna!"
"Yeah Duke...me too!"
And then both of them hit orgasm, slumping over one another as they finished, Terry breathing harshly but still able to get back up shortly afterwards, while Duke was almost hyperventilating and out of breath, shivering and looking like this was the most intense orgasm he'd ever had.
Sarah and Jess broke into a thunderous applause and Jess commented, "Wow...just...wow. I didn't see that coming. You guys have earned a reward. Duke? You feeling okay there?"
Duke finally got himself in order, and groaned, "...Ohh fuck, Jess..." He had not expected that to feel half as good as it did, but even with that in mind his romantic affections still aimed at Jess. He just now realized fooling around with Terry felt really, really good. He would have to do that again some time. Maybe even invite Terry into his and Jess' bedroom for some bisexual fun.
Terry meanwhile was lightly kissing Sarah - even after watching Terry do that Sarah had no doubts about him. Sarah asked, in a rather nervous tone, "How...how'd it feel, Muscles?"
"Felt...better than I thought it would. Mind you I'm still straight and I'm REALLY looking forward to our time together, but..." Terry trailed off, wondering how to articulate it.
"Don't worry about it. It was really great to watch, and uh...honestly? If you guys wanna do that again, I want to watch it again." Sarah whispered to him.
Terry blushed a little again, and wondered. He was now standing with his beautiful, hot girlfriend who wanted to please him, but he also had amazing, athletic Duke who might be amenable to another fling. Maybe he WAS a little bit bisexual. He wouldn't think of doing this with literally any other guy.
"So..." Terry started, speaking up, "Now that the...entertainment is over. Uhh, what do you guys feel like doing next?"