Setting it out like that led me to thinking about how I had managed back when I was still plotting by feel, without trying to plan it. The last book I wrote that way has been published under the name of “Living Doll” (I didn't pick the title!) and it's interesting with hindsight to see how I made the plot work. This is just my own self-indulgent musings, so I don't promise it will be interesting...

The idea was to make a real, working novel out of the ancient BDSM cliché of the kidnap victim who learns to love her captor. The hero starts with an obvious problem – to convert the heroine from captive to willing slave – but that wouldn't carry more than a short story, so I raised the bar high: he's not a rich charismatic experienced Christian Grey, he's an 18yo with congenital dwarfism that's left him short and ugly with parents who treat him like a sick child. (I wanted him to be a precocious 15 to make it even harder, but I hit my publisher's rules on underage sex.) And he's got a tight deadline, he's got to have her on his side in ten days.

Even then, his plot line is basically going to be a straight-line task, though I managed to throw in a few curves. I particularly liked the scene where, late on, he fulfils the fantasy of taking her out in public sexily dressed, and gets attacked by a predatory drunk and only saved by his slave's fighting skills, so they both have to come to terms with a threat to their roles and their self-images.

But left to itself that's still not much of a plot, so right from the start I made the heroine not just a fantasy sex object but an equal protagonist with her own story arc. And hers is really interesting, with her initial goal being to survive a horrible ordeal, then having to come to terms with starting to enjoy what's happening to her and wanting to submit to her captor, with all the self-reappraisal that involves. So the story became the entwining of those two plot lines and the growth and changes that both characters go through.