These have non-human protagonists, animals that, nowadays, we don’t want to over-sentimentalize or make into humans in animal suits. Predators hunt, prey has to defend itself in any place not a zoo, and Bambi won’t have any clue as to who his father is.
Of course, children’s fantasies and humor are always another matter. In that case we may be getting into animal fables or anthropomorphized animals, where the squids and foxes are indeed humans in beast suits, acting and thinking like people in similar situations. These range from Aesop’s fables to The Lion King. “Furry fandom” is its own market, where the animals become upright and bipedal with hands and other human anatomy, though usually with fairly animal-like heads.
Old Yeller is an animal story. Watership Down is a furry.
Fantasy Erotica, Historical Erotica, Science Fiction Erotica — the main thing that changes is the setting. Think how to put this to use. SF erotica has the possibilities from sex in zero-G to those of wiring your brains together. Fantasy — well, anything is possible with magic. Historical erotica needs to make use of the cultural peculiarities of the time.
Just remember that good erotica is still a plotted story. Romantic Erotica even introduces the limits of a romance story, with the h/h needing to wind up together at the end in a good relationship. Of course, that may be hero and hero, or heroine and heroine, or h/h/h, or more … Werewolf romantic erotica can get complex, what with pack politics. But fun.
Note that one of the biggest sales markets is women’s erotica, especially romantic erotica. If you’re thinking salable, check the guidelines at various publishers. They usually start with no pederasty (that’s illegal too many places, and I mean publishing the stuff can catch them jail time) and no real rape (the nasty, scary, not-sexy kind) though the sex can get pretty coercive in a nice way. A lot just depends on your bent and that of the readership. S&M or bondage are legitimate variations on the theme: just check if your chosen publisher does that or not. Some are more vanilla and some are much farther out there. Some have specific lines for different levels of kinkiness. (Kinky = The speaker/writer doesn’t do it but it might be interesting to read about. Perverted = They’re not interested.)
Comedy, Satire, Humor
This literally has its own rules, those of What Makes Something Funny. Some people know this by nature and some take it as a college writing class.
The longer pure madness runs, the harder it is to maintain. You start needing to ground your craziness with things like obstacles, plot, characters the reader will care about enough to come back to tomorrow for the next chapter. So it does also need to address some of the regular rules of fiction.
Since I’m not going to cook down a semester class here in the rules of comedy, let’s concentrate on the differences between the three forms listed, if any.
Comedy and humor/humour can be used interchangeably, depending on what the advertising department thinks is wise. We might say that humor is the funny side of realism, while comedy isn’t quite so concerned with keeping it within bounds. Terry Prachett’s Disc World books are comedy fantasy, but I wouldn’t call them humor. I was told the Stephanie Plum books are funny, but after reading the first three, I wouldn’t grant them more than humorous mystery. I’m told it’s their crazy characters, but I guess I’m too used to hanging with people crazier than that.
Really, “comedy” entails anything meant to get a laugh, while “humor” is a quieter sub-set of it.
To get historical on you, because some people will, insisting it still matters (which is doesn’t), “comedy” originally was the opposite of tragedy and encompassed all tales that didn’t end badly for the protagonist. That’s in ancient Greece, 2500 years ago, and we use it differently nowadays, for funny stories. “Humor” is newer, a Renaissance word, where they wrote plays and essays on how different people displayed their particular “humours,” meaning personalities based on the four elements. Even this changed rapidly, to mean just personalities without having to justify their chemistry. But you can see the remnants of these in my definitions, in that humor is still an observation of real-type people, even in extreme situations, while comedy is anything funny. In movies, let me point to screwball comedies like My Man Godfrey or It Happened One Night as humor, and the Marx Brothers as comedy. But they’re all called comedies!
So comedy is the entire field, while you might use the term humor for anything on the more realistic end of comedy.
Satire is specifically making fun of something by presenting it in fiction, in exaggeration or in complete disguise. Catch-22 satirized the military and mental hospitals by showing an extreme version of them. Ernst Bramah satirized Victorian England in an atmospheric and convincing, but ultimately inauthentic, version of ancient China, in his Kai Lung stories — complete disguise. Voltaire’s Candide satirized the philosophical stance that “this is the best of all possible worlds” by having a philosopher constantly explain how the horrible things happening to the hero and heroine really were for the best.