Have you noticed that once the sexual tension is over in a television show, the ratings drop? I may be showing my age, but does anyone remember the shows Moonlighting and Who's the boss? Once the main characters did the deed, it was like the writers had nothing else to write about. The hero/heroine acted like they got bored with the relationship after sex. And I got bored too.
But I noticed that doesn't seem to happen in books. There are tons of series out there that leave readers salivating for the next story. Some of them involve secondary characters from previous books, and some of them don't. But there's always something there that draws us back. Something that makes us want to see if the main characters really lived happily ever after.
I'll be the first to admit it. I'm a series junky. Books, not tv shows. What's your favorite series? Books or tv.