There’s any amount of How To Be A Writer advice out there which tells you to get yourself a series. Everyone loves a series, after all (even if the series creator only has one idea and is milking it beyond rhyme or reason. I do recall, however, reading an editor’s musings a while back about how you should never announce in your cover letter that the attached story marks the debut of your ‘new series character’. I think said editor may have had a 
point.Because I read fast and am as impatient as fuck, I have never been very keen on getting to the end of a book I’m really enjoying only to discover it’s the first of a trilogy, quintet or more and I have to wait maybe up to a year to know what happens. Absolute Rule 1 of creating a series is getting the balance right between tying up the loose ends of part 1 and making the reader at least moderately interested in getting to part 2, if you’re writing a series of novels. Yes, if you’re going to bring out an episode a week or thereabouts, you want a cliffhanger that has them all biting their nails, but 60 000 words’ worth of story shouldn’t just grind to an arbitrary halt.
Of course, one way to create and maintain a popular series is to have a central character. This seems to work best for crime novels: ever VI Warshawski or Inspector Banks story works perfectly well on its own and the little bits of side- and back-story carried over from other books are just seasoning, making the experience richer, if you don’t feel inclined to seek out all the other 
volumes. Some erotica writers can sustain a protagonist’s story over three or four books, but it can be more of a challenge to keep things interesting if your main focus is on whether a heroine can end up with the right hero or not and you want to stretch it out indefinitely.
There was a point, when I embarked on my second stage erotica writing life, where I thought i had set up a universe that would make a perfect ongoing playground for unlimited books. I had a central couple, whose trials and troubles made up the first story i wrote; i subsequently did an additional short story just because I thought of something they might do one day, and then found that some of the secondary characters could do more as well… More short stories and another whole novel followed. And then, lazy unproductive sod that I am, I sort of forgot about the lot of them, and now it seems that the world has moved on too far and too fast for me to go back into that particular storyzone without it all becoming unbearably stilted. So I’ve dragged the original one out of its dusty corner and refurbished it ever so slightly, and after that I’m going to jump across the universes and find somewhere else.
What’s your favourite erotica series? Share it in the comments…