It was the cumulative result of everything they'd been doing, the fact that he'd been trying to hold on for as long as he could before, the excitement that she had racing through his body, and even more. He was too worked up to keep going, it had taken everything he had not to give in already.
His hands were on her hips, pulling her back against him, and he finally couldn't last. He tilted his head down and groaned loud as his orgasm hit him, hips jerking forward, lips pressed together tightly.