Sex in The Time Traveler's Wife represents a physical connection essential to the intimacy of the characters. Sex helps Henry stay in the present, because he feels closer to Clare. For Clare, sex with Henry is tangible proof of his existence. But how much sex is enough? Clare actually poses that question to Henry and she's not the only one. Some critics of the book claim that the sex scenes don't serve the story. Then again, others claim that it's central to understanding the tale. So which is it? You decide.