With that realization, Jeremy simply gave in to necessity, and held himself as still as possible while trying to get control of himself again. When a couple seconds had passed with him staying motionless, Dawn finally asked "What is it, Jeremy? What's wrong?"
Blushing fiercely in his embarrassment, Jeremy hesitated several seconds before finally answering "I, uh… I'm kinda having a problem, and just need to hold still for a minute…"
"But why?" Dawn asked, confused.
Trying to not have to admit what the real problem was, Jeremy simply told her "Because it feels so good to me to be inside you like this. Too good, almost. I just need to not move for a minute so I don't… disappoint you or anything."
It took a few moments for Dawn to understand what Jeremy was getting at: that he was close to cumming in her. She had to think about it for another couple of moments (she was a bit 'distracted', after all!) before remembering that it was a lot easier for Jeremy to get excited – and even finish – than it was for her. Her first thought was to simply tell him to go ahead and cum, since she knew that he'd last longer the second time anyway. But she quickly realized that climaxing so soon and so easily after getting his wonderful cock in her would only embarrass him and make him ashamed; she knew from everything that had happened up to that point that he he didn't want to disappoint her any more than he'd wanted to hurt her.
So despite her almost overwhelming desire to tell him to go ahead, she decided to be patient a little bit longer – she'd waited this long, so a little more wouldn't kill her. When she spoke to him again, it was to say "That's okay, Jer. If that's what you need to do, then it's okay with me. Is there anything I can do?"
2
Even that brief conversation with Dawn was enough to let Jeremy pull back from the edge a little bit, so it was with considerable relief that he answered "Thanks, Sis. No, there's nothing you can do; I just need to, um, kinda catch my breath."
Though he didn't know it, it took Jeremy almost two full minutes to learn to deal with the indescribable feelings emanating from his cock; once he did, though, things went a lot faster.
It seemed to Dawn that it took just short of forever before her brother "caught his breath", but she finally did feel him start to move in her again – and it was great!
Jeremy's first efforts in his sister were slow and gentle, both to give her plenty of time to get used to having him in her and moving, and to make sure that he wasn't going to "go off" too soon. Once he was sure that those two concerns had been addressed, he readily increased his efforts. It wasn't long before he was sliding nearly the entire length of his erection in and out of the delightfully hot, wet, and tight sheath of his sister's womanhood – accompanied by Dawns pleased moans and enthusiastic arching up of her pelvis in welcome to his thrusts.
Dawn was almost willing to believe that she'd died and gone to heaven, it felt so good to have Jeremy's penis moving in her. It seemed like she could feel every vein and ridge on it as it slid back and forth through her opening; each time Jeremy pressed himself into her, she could feel him bump against her achingly-erect clit and the sack of his balls slapping against her ass. As nice as she'd dreamed it would feel to have a guy inside her, it wasn't anywhere near the reality she was experiencing. For having experienced the pain of having her hymen broken so recently, she was amazed at just how good it felt to finally actually be fucking. Even as she could feel herself moving closer and closer to her first "real sex" orgasm, she couldn't help but think that she – and Jeremy! – had been right to wait. She knew that it was only because both of them knew she was "safe", and they had the time and place to do it right, and (most importantly) the love that they felt for each other that she was able to enjoy what was happening.
Jeremy didn't know that it was the way he was pumping himself into his sister that was exciting her so much – and the truth be told, it probably wouldn't have mattered, anyway: he was finally getting the chance to actually fuck for the first time, and once he was sure he wasn't going to cum too soon, that was pretty much all that mattered to him. All he was really sure of was that Dawn was responding to him the way he'd hoped (he could only figure that she liked it; the idea that she might be responding to what he was doing was beyond his ken, young as he was), and that she felt pretty damn good to him. Good enough, in fact, that he was getting close to unloading himself in her.
The increasing frequency – and force – of Jeremy's thrusts was driving Dawns mind farther and farther away from being able to think about what the two of them were doing; leaving her aware only of the physical sensations that threatened to overwhelm her: the feeling of being filled and emptied by his penis, the way her nipples felt as they were dragged across the smooth surface of his hairless chest, and (most of all) the intense and indescribable feeling of his pelvis bumping against her clitoris each time he thrust into her. The sum of it all was so much more than what the she'd experienced when the two of them were together before that she knew that her rapidly-approaching orgasm was going to be far, far more than any of the ones she'd had before.
For his part, Jeremy was also aware of Dawns hard nipples as they drew Lissajous patterns on his chest in time with his efforts. He was intensely aware of how hot and tight Dawn was around his erect cock; he was even faintly aware of the liquid noises being generated by his plundering of his sisters incredibly wet treasure – and the sounds of pleasure and encouragement she was making. As was to be expected, there finally came the point where the incredible pleasure radiating from his manhood got to be too much; after a couple of fast, almost savage, thrusts, Jeremy tried to stuff as much of his young cock inside his sister as he could before the first wad of his jism erupted deep inside her.
Jeremy's last couple of thrusts were almost enough to push Dawn into her release; indeed, if Jeremy had managed even one more of them, that would have been enough to do the job. When Dawn felt Jeremy spraying her young vagina with his seed, she thought she was going to miss out – except that the sudden realization that he was cumming in her was enough to do it. With a near-scream of arousal and pleasure, Dawns nubile young body gave itself over to the incredible joy of her first coital orgasm.
The pleasure Jeremy was feeling was greatly amplified with the start of Dawns climax: the sensation of her already tight vagina clenching around him was something that he couldn't have even imagined before – and wasn't all that sure he wasn't imagining, in fact. But that it continued, and in time with the waves of pleasure that he could feel coursing through his sister underneath him (and gasps and groans she made, too) told him that it was real enough. It was only as the last few spurts of semen were leaving him that Jeremy realized that he'd managed to give Dawn as much pleasure as she'd given him – pleasing him immensely, and making him love her all the more.
The first spasm of release to hit Dawn nearly overpowered her, it was so intense. The ones that followed were marginally less powerful each time, but certainly no less pleasurable to her. By the time it was over, she was covered in a fine sheen of perspiration and gasping for breath – and thoroughly satisfied with her first experience of actually fucking. Jeremy was still holding himself over – an in! – her, something that nearly brought her to tears before she wrapped her arms around him and hugged him as hard as she could.
Jeremy felt it as Dawn let her legs unwrap from around his waist, only to be surprised by the ferocity of the hug that quickly followed. When he was finally able to raise his body enough to look down at her, he could see the joy on her face and tears in her eyes as she told him "Oh, Jeremy! That was wonderful – it was so much nicer and better than I thought it would be! Thank you, thank you, thank you!"