Like futuristic, fantasy, and paranormal romances, time travel romances take place one step beyond the "real" world. Unlike those other stories, however, time travel romances are more likely to be popular with the typical romance reader. Readers who would hold up garlic every time they see a vampire romance might still enjoy time travel romances. Maybe it's because so many readers have the fantasy of traveling back to a more romantic age. That might explain why it's most often the heroine who goes back in time.