Their sexual marathon finished, Matt had went outside to catch his breath, dressed in a tank top and shorts - damn but he was not regretting going straight for Kelly. She was voracious, and her sexual appetites were astonishingly well diversified. He'd never encountered a girl so eager to peg him, and eager enough to receive it in turn. Usually the guy had to beg for anal. It was refreshing for the two of them to be so on point with what they wanted. Matt wasn't doubting he was gay - just that maybe he was less a 9 on the Kinsey Scale than he thought he was. Maybe more of an 8...
...And in no small part due to who he saw outside, standing in torn up clothes and wearing a well made jacket for the same football team Matt played on. His eyes went wide as saucer plates he could swear. His vision went from the hunk's broad, strong features on his face, together with bushy hair and slight facial hair, to the enormous musculature trying to hide behind torn up clothes, the erection the poor guy was desperately trying to cover up in the face of company, and eviscerated shoes.
"Woah." That was all Matt managed to say. "Hello big guy..."
"I-I'm not gay, I swear!" Was all Dale managed to say, flinching and visibly anticipating something based on his presentation and how he looked. Covering up a boner, and looking for all the world like the dreamboat jock fetish come to life.
"Nobody said you were, just appreciating the view. Chillax, big dude." Matt started, and examined him. Big guy looked pent up, definitely nervous, really out of his element. Then he realized something. He checked out the hair again, looked at the guy's eyes and the shoes. He recognized those shoes. Those clothes... "Dale?"
Oh I am so fucked, Dale thought as he quivered in place. "Dale? Uhh...huh...who's...er..." He couldn't even bring up a good excuse or a convincing cover story. His mind blanked right when he needed it the most, "Yeah. Yeah its me. I-I don't even know how I got this way. I just ended up like this. Like, all of a sudden...I'm like, I'm excited, but I'm scared and---I got a fear boner."
Dale looked down and Matt swore. This was gonna be one hell of a doozy to explain to Kelly. That somehow her little brother was now a big buff dude standing outside, and how he was gonna need some new clothes.
"And again," Matt said, "Nobody blames you for you being a sexual being at this age. About eighteen, you're a jock now, you're gonna be springing wood at someone complimenting your body, kissing you, it's a whole thing with how much test you're making now."
Dale felt like collapsing, but his need was sharp and cut through everything else, and he looked at Matt for a moment. He didn't know how to say this in a way that wasn't absolutely cringe inducing to him, but here he went, "I-I gotta cool off...can I use the bathroom to uh...take the edge off?"
"Dude, just say you need to beat your meat." Matt chuckled and led Dale inside, guiding him to the bathroom.
Dale quickly slid the door shut and removed all his more ruined clothes and shivered as he wrapped a hand around his organ, not a single specific fantasy played out through the nerd-turned-jock's head, just the desperate need coursing through his body. His nipples looked like they were erect, and his body outright wavered on unsure feet from the new sensation. There was a world of difference between Dale's old body and this new, oversexed dreamboat Adonis body. It was made for laying into cheerleaders and occasionally fooling around with fellow athletes and coursed with testosterone and ready made sexual needs.
Dale moaned first, and then went into a series of moans and grunts that Matt could hear through the door. He wanted to apologize for it, but good fucking GOD he needed to cum. Dale knelt over and crudely humped his hand, desperation leading him to a rather indignified position. He barely sounded coherent on the other side of the door, but he was really finally getting to enjoying this. It felt so good Dale pumped an arm into a flex...
Kelly came downstairs after getting in some rest after the sex with Matt, and heard the moans from the bathroom. Seeing Matt standing outside of it, she asked, "...What's going on in there?"
Matt walked over and guided her out of the room, stating in a rather even, prepared tone, "...I will need to explain this one to you. You're...probably not gonna believe it. But not much about what happened leading up to this makes much sense."