It's been a while since I've written, and I can honestly say I've had no new insights into writing smut until two days ago. I just finished the first draft and edit of "The Devil and Delilah", which is going to start yet another series of mine (really, brain, you have to keep giving me ideas? Can't you let me finish a series first?), and a writer friend of mine looked it over. I was pleased to see that most of the corrections weren't of the 'your eye is dumb and glossed over that' variety, save for one, and they had to do with changing up a few words or clarifying here and there. I was chill with that. They were all very useful corrections, and I cannot thank him enough for doing that.
However, the biggest complaint was something that can't be fixed easily. He asked why it was so short when it felt, to him, that it was just the beginning. It comes in at about 12K words, which is sizable without being overly large, and is definitely longer than most erotic shorts out there. It IS the beginning of the series, and I feel it's complete in an of itself while he maintains it feels too short or just when the story is getting started, it's done.
That got me to thinking about the different books out there, especially for erotica, and why they are the way they are. There basically are three different kinds: shorts, serials, and novellas/novels. Shorts are just that... they are short stories, one-offs, with different characters in each story. They may all be related (ie, my femdom series. Every story has a different set of characters in it, but they are linked together by the kink, hence it's called an "anthology" series), and many erotica authors do write a series of stories in a particular kink or fetish to bundle into a collection later on. Serials are short stories to novella length pieces that have the same characters moving from situation to situation. The Janus Key Chronicles is a serial. They range from 8,500 to about 15,000 in length, depending on how long it takes to tell that segment, and then that "book" ends. Many, MANY erotica writers write serials because it draws people in, and when they read the first one, they often follow it up. The last, of course, are novellas/novels, I would say pieces over 25,000 in length or so which can either stand alone or be part of a series. Everyone knows what a novel is, so I'm not going over that, but I do lump novellas in with them rather than serials because very often the writers in this category put a lot more plot and character development in them rather than wall to wall sex, or JUST get the characters in situations to have sex, which is often the point of serials and shorts. Two examples of mine would be The Queen of Swords or Operation: Thrustmaster. There are plots in both, and while one is more tongue in cheek than the other, the entire point is to tell this story which happens to include a fair amount of sex. Since The Queen of Swords turned out much more serious and I felt could stand up without the sex, I put it into a non-erotica category. Operation: Thrustmaster is a bit of the opposite: the whole reason it was written was to have spy sexy times, and thus, it's erotica. And believe it or not, at least in one place the plot can't move forward without the sex. It could... I guess... but the whole point was for sexy times.
So, which is better? The answer is many and varied, and if you ask someone else, you'll get a different answer. I prefer serials and novels to shorts. I have a lot of stories to tell and some will take a lot of space to tell and some won't. Back in the days of "KU1" where when the reader read the first 10% of a book, the author would get paid anywhere from $1.35 to $1.50, shorts was where to be if you wanted to make money. You'd want to aim around 4K words so that you'd get paid after only a few page turns on a kindle. Now, with "KU2", the author gets paid per page read, so that it's more advantageous to have a longer story which captures the reader's imagination (or other parts) and keeps them reading.
I don't like shorts. I might come up with stories here and there inspired by things. The Cosmic Erotic series is two sci-fi shorts that I had inspiration for. I wrote them to be as long as they needed to be and that was it. I had no further plans to go with either character. The JKC was conceived as a serial from the beginning, and while they may be considered "shorts", I consider the whole series as one big long book, that I'm just publishing a chapter at a time. I did a whole series of femdom shorts, and while I like femdom, I grew really tired of having to think of new situations and new characters every time. It's just not my thing.
At the same time, while I love writing novels, they are much, MUCH harder to do great. I can keep track of stories in a serial much better than I can with what's happening in a novel I'm currently writing. I have invested in Scrivener to help with this, and so my philosophy might change eventually as I become accustomed to using it. When it comes down to it, I am writing the story as long as it needs to be and no more. I might make more money padding it, but it's not necessary.
So, serials are the way to go? Not necessarily. It really depends on the writer's style and time commitment. If someone has the time to write a novel, I would say to do it! However, many aspiring writers don't, and writing a serial can be a way to get instant feedback on a series or world without the huge time commitment novels require.
The other thing to consider too is that writing short stories and writing novels take two different sets of skills, believe it or not. With a novel, you have the luxury of building up tension and character arcs. With a short story, you need to get right to the action, yet still explain who these people are and why we should care about them. A serial is a middle ground there, requiring the skill sets of both.
In the end, I think authors need to go with what works for them. What I would personally recommend is working on shorts first, to simply build up your writing chops and get used to disciplining yourself to write every day. If you are not going to finish the novel, or if you can't focus on it for that long, shorts or serials might be the way to go for you. If you can focus, and have the time to do so, then novels would definitely be the way to go. In the end, the most important thing to do for an author is simply to write and to tell that story, in whatever form it's in. I personally prefer serials, because it allows me to get paid quicker, but still tell the long story. I get involved in characters, and I really don't have the time to invest in too many novels. Hence, writing about characters in bite-sized pieces really appeals to me.
When I dreamed up the Delilah Devilshot series, I envisioned starting her off in tragedy right away. However, upon thinking about my beta reader's feedback, I may lengthen the beginning slightly so we see more of her life before tragedy strikes. I won't guarantee it'll add more than a couple thousand words, at the very most, but at least we'll have some attachment first. Still thinking it over because to me... it starts in action, ends in action, and she's moving forward. Although it might be short, one would hope it entices readers to read the next, not that the next is out quite yet. It should be relatively soon after the first, though. If I would sit down and write out Delilah's story in novel form, it would be a huge mother fucking novel, and it seems daunting looking at it from that perspective. *shrug* All I can say is to find what length of story feels right to you, and work accordingly.