In comments on two -- Edit: make that 3 -- recent stories, readers have called for more about the characters.
Now, I always take that as a compliment. I've succeeded in conveying enough of characters that some readers treat them as real and want to know hat happens next.
the two stories are otherwise very different, though.
I stopped Your Zee at a point where the main characters' relationship is quite precarious. (Partly because I don't really believe that it can turn into something lasting.)
Hath Eyes has characters who are going to get married in a while. I don't feel that taking them through their long engagement will interest either the readers who have requested it nor -- and I'm more dedicated to this -- myself. I could write as tory about their marriage later, but I probably won't.
Like a Gentlewoman ends with the characters married and with a baby. That's the end of every Regency Romance that I've ever read. It's certainly the end of a story. I don't plan to write another story about them, but -- even if I did -- it would be another story. (And, I might point out, SOL doesn't have a story code for stories about faithful married couples.)
I have written a few series, but I stop a story when that story has been told. If the hero is not named Adam, a prequel is possible; if the story doesn't end with thermonuclear war or the Sun's going nova, a sequel is always possible. That doesn't mean that I'm called to write it.