Some readers say they skip the sex scenes in romance novels, but often authors reveal the most about their characters while they are having sex so it adds to the experience of the entire book to read those scenes along with the other times when the hero and heroine are clothed.
For example, here's a snippet from Miranda Neville's The Duke of Dark Desires:
“Why did you stop, Julian?” she moaned. “Don't stop.”
“I'm collecting myself,” he said tightly. “I don't want to finish before you.”
“Don't worry about me.”
Julian added the words selfish oaf to the list of epthiets attached to her ravisher. “I most certainly will.”
That tiny snippet reveals how Julian feels about his heroine, even though he's been the titularly-named Duke of Dark Desires throughout the book. He's changing, even though he doesn't realize it himself.
What other authors reveal truths about their characters during sex scenes?