An Incubus is a sex demon, plain and simple. They feed off of the sexual moods of humanity. But once humanity found out the Incubi existed, a big war started to get rid of either one species or the other. But there's a problem. Succubi (female counterparts of Incubi) and Incubi need the sexual energy of humans to fuel them, and the men of the human race are dying very fast due to war depleting resources, and everything went to the women. Without men, the human woman can't reproduce and therefore can't supply the demons with the sexual energy needed to keep the demons alive. So some sort of alliance has to be made, between the king of the Incubi and the queen of the humans. An alliance that requires marriage.
Now, I've had too many people asking ridiculous questions. Here is the plot but stripped:
There's a male character, the Incubus king.
There's a female character, the human queen.
Obviously there will be challenges in this arranged marriage because the humans think Incubi are disgusting, and inappropriate, and just much too uncivilized. They aren't, but you know. Humans can be morons.

A mysterious stranger rescues a princess from drowning as a child. Her father, the King, offers the young man anything in his kingdom as a reward and the man shocks them all by choosing the very Princess herself. The King, unable to go back on his word, agrees to the arranged marriage. Years and years later, the Princess grows up and the mysterious stranger returns on her eighteenth birthday for her. Much to everyone's surprise and horror, the young man has not aged a day since last they saw him. And when he takes the Princess home with him as his bride, she realizes there is a lot more to him than meets the eye.

It’s the year 2285, and the world is in turmoil. The U.S. Has been shunned by the rest of the civilized world and has become a dictated union. Global warming, world wars, and economic collapse have turned the States into one of the most dangerous places to live. Only 1% of the population is wealthy enough to have homes, cars, decent food and clean water. The rest of the country is living in half-homes and has to scavenge every meal.
This dictatorship locks away dissenters, the sick, the old, and the mentally unstable in concrete prisons underground. The food is poor, the living conditions are nowhere near humane. One girl among these prison outcasts is treated especially terrible. At a very young age, she developed a power that made it impossible for anyone to touch her skin. The government didn’t know what to do with her, so they tossed her in prison to let her rot. Now, ten or more years later, the government finds that they need information about a certain Resistance group. They can’t torture it out of the prisoners in any traditional way… so what if they use her?
They send their young, up and coming general to collect her. He enters her cell to find a mad creature, incapable of speech and the most basic human interaction. He thinks her a beast, a monster for her curse and the job she’s given. But will that change in the next few weeks as he wipes away the grime and teaches her how to be human again?

To be marked with a crescent moon on your face is to be marked with a death sentence.
The Tainted are a group of people that live just outside the walls of a city by the name of Kardain. Their lives are filled with misery, ridicule, and poverty. They endure this only to be killed. Every year, groups of Tainted citizens are marched to the town square to be publicly executed as ordained by the King.
Legend goes that the Moon Goddess Diana was upset at the people of Kardain, thus she cursed the city. The mark of the crescent means he who bears it is an abomination in the eyes of the Moon Goddess.
However, the Moon Goddess never intended for this to be a curse. Rather, it was a blessing. The human race's fear of the supernatural turned her gift into torture. The Tainted have powers that are unlike anything the citizens have seen. When first bestowed upon the people centuries before, it incited terror and rejection.
Thus a ritual was created - the Cleanse - in hopes that the city would be freed of its curse if the Kardanian people killed enough of the Tainted. Unaware that they had misinterpreted everything, this continued for over 250 years. This year will be the 267th Cleanse, and a new King has come to power. He is young and carries new ideas. However, this does not mean his ideas are better than those held by previous rulers. Put simply, he finds the Cleanse, in special cases, a waste - especially when a pretty face is involved.

Setting:
The Tainted that have been collected for this year's Cleanse are being brought before the newly crowned king. This is his first year hosting the Cleanse, and he intends to do things a little differently.

The Offering is made once every decade. A dozen women, having just come of age, will be presented to the Demon as sacrifices. His One Choice will descend with him into the Shadows and serve him devoutly over the next decade. And so his wrath will be forestalled, and the village kept safe for the following ten years, until a new Offering is made. As per tradition, the Offering will take place precisely at sunset.

Girl: You wake up in a castle, and you don't know where you are. There are so many things out of place, and your memory is blurry, so you really just have to connect the dots. It's not that hard once you notice a few key things: Your clothes are gone, replaced by terribly revealing underwear. Oh, and there's a man sleeping beside you. After learning that you've been gifted to this pervert as some sort of toy, you rebel as much as possible.

You're the Crown Prince of (some kingdom) and for some reason, you’ve been given a slave girl to do with what you please. You do your best to wrangle this girl into submission but she’s like some wild beast.
And things progress from there.

Girl: Your parent(s) die. Filled with grief and anger, you are sent to live with your uncle/grandma/some other relative in a tiny town in the middle of a ridiculously dense forest. You are told never to go into the forest at night, and especially not alone. But filled with rebellion from your parent(s) death, you go in there anyways. You run into a man, a man who has the ability to turn into a wolf. He kidnaps you, and shows you his pack. Your world is turned upside-down by this shocking revelation. You're being pulled and tugged in a million different directions, and through it all you fight through your growing attraction- and fear- for the man who took you, even though he's more beast than he is human.

Guy: You're a werewolf. Not the bitten kind, the born kind. Your pack lives in the forest surrounding the town. There's a treaty that basically says that the werewolves will leave the townspeople alone and vice versa. But if a human enters the forest, they belong to the pack. One night, while you patrol, a new girl to the town enters the forest and you claim her before your pack mates. You show her your pack, keep her safe from the harsher wolves, the ones that dislike humans. Along the way, you discover for the first time exactly what it means to be human.
Also, I have a thing that must be explained.
You know the inner voice everyone has, like a conscience that tells them right from wrong? Well, werewolves have that too, but theirs is broken. They don't have an off switch, and their inner voice is angry, horny, and slightly violent. It's also very persuasive. Depending on how a wolf is raised, that voice can either be tamer or wilder. When the inner voice is wilder, it's harder to ignore, thus creating a werewolf that is moody, easily frustrated, and a bit bipolar. Someone who is harder to control.

Important stuff:
These werewolves are, for the most part, just human beings that can shift into wolves. They don't have an extended lifespan or slowed aging. They are slightly stronger, but not to an insane degree. Some of them have a strong enough sense of smell that they can scent things a few miles away, or scent moods and emotions. This is rare, though. They just look like really big, but otherwise normal, wolves.

The world has fallen to ruins. Very little people have survived. People can't remember everything about themselves. They're all lost, and confused, trying to survive. Day by day each person goes to find their own Pieces. Each person's Pieces eventually become an object that will completely restore their memories. These Pieces are hidden throughout the world, and each person's Pieces look different. Some people are out to destroy other people's Pieces, or help others find them while they look for their own.
This has been immensely successful for me in the past
So this would be a good few years after the apocalypse.
There are little towns and settlements.
To be clear, let's say that everything short of zombies and aliens destroyed most of humanity. Earthquakes, tsunamis, biological warfare, the whole shebang.
The way I have done this in the past is that the male character is a bounty hunter, or a mercenary. He's being paid to either kill or capture the female character for whatever reason. The world was inherited by psychopaths, so they might just want her because she's pretty.
Obviously, he finds her, and stuff happens.

Girl: You're a princess. In your kingdom, magic is just barely tolerated and your father is trying to get rid of it. But you yourself possess magical powers. You've been kept away from people your whole life, an embarrassment to your royal family. One night, you run away. You travel a nearly impossible distance, even across an ocean, to find the son of a powerful sorceress who you believe can teach you to control your power. But what if it turns out he doesn't want to?

Guy: Your mother was the most powerful sorceress in the world. A true legend. And because she was the best, she raised you to be even better. No child of hers could be anything less than perfect. She treated you cruelly, punishing you with her magic when you made mistakes or refused to learn. You've come to despise all magic-users and magic itself, causing you to never use your own powers if you can help it. Then, a girl comes to you, desperate for your help. She's so young and naive. She won't survive on her own if someone doesn't teach her how. But how can you teach her to control her powers when you hate yourself for having the same gifts?

Okay, so basically the zombie apocalypse happened almost twenty years ago. No one old enough to remember First Night talks about how it all happened. There are fenced-in settlements all across the ruin of America, some of them large and some of them small. People lock their bedroom doors at night in case of death, because no matter how you die, you become one of them.
The world outside the fences is called the Rot and Ruin. Most everyone pretends it doesn't exist. They're content to live inside the walls, like cattle. They're in denial about how the world is now. Except for a few. Bounty hunters, souls so damaged by this new world that they just don't fit in with everyone else. Killing their targets- not always the zombies- is all that gives them peace. And not all the bounty hunters are good. Most are corrupt, evil. But there are a spare few, those who call themselves 'closure specialists' that hunt zombies that people knew in the world before, and putting them to rest in the most humane way possible. Then there are Loners, those who live in the Rot and Ruin and carve out their own niche of hell. They're territorial and vicious, and often kill on sight.

(Based off of the book Hunter, by Mercedes Lackey.)

They came after the Diseray. Some were terrors ripped from our collective imaginations, remnants of every mythology across the world. And some were like nothing anyone had ever dreamed up, even in their worst nightmares.

Monsters.

Long ago, the barriers between our world and the Otherworld were ripped open, and it’s taken centuries to bring back civilization in the wake of the catastrophe. Now, the luckiest Cits live in enclosed communities, behind walls that keep them safe from the hideous creatures fighting to break through. Others are not so lucky.

There are those born with magic, or manna, and have the ability to call Hounds to their aid to help them fight the Othersiders, the monsters. These people are called Hunters, and they protect every human from the terror of the beasts.

Mandala: A mark burned into the backs of a Hunter’s hands that help them call forth their Hounds. Each mandala is different depending on who the Hunter is. If a Hound finds their Hunter unworthy, they can take back this mandala and tie themselves to another Hunter.

Hounds: Beasts from the Otherworld that hate other monsters. They take all different forms, and there are different classifications. They tie themselves to those with the potential to hunt, and form a pack around their chosen Hunter. No Hunter has ever had more than nine Hounds.

Aleksandra gave a small start and half-turned to watch Forgefire enter his chambers. She cursed herself for showing such an interest in his weapons and hoped he hadn't noticed, but she wasn't a lucky sort of person. Hence the stinging mark on her foot and the eleven years of her home being a dagger in her hand.

As Forgefire prowled closer and examined his cloak, she noticed that he'd washed the grime from his skin and hair, and that he was actually much more attractive than she'd first thought. He looked much like a bear himself, burly and charming. She was certain many other women would not find his looks appealing, but she knew what strength, cunning, and kindness looked like, and they were all the qualities she saw when she looked in a mirror. She knew how battle and death could mold someone, and oftentimes the result was not kindness. They were a rare breed, and it appealed to her immensely.

And with that thought, she completely snuffed those feelings and shoved them into that handy little space in her head she reserved for such nonsense.

Oh Saints, he'd noticed her staring at his weapons. Of all the Devils-damned things— she had a death wish. That had to be it. Or it was the drugs still tearing a path through her system, making her all muddy-headed. Well, no point in delaying the inevitable. If he inquired as to her true identity, maybe they could come to some sort of arrangement? His protection for her services. And he might not maim her as much if she explained why she lied to him.

With a resigned sigh, she turned and drew his sword. She really didn't like swords, as they were one of the few weapons she had no affinity for. Daggers were her forte, as were staves. She was decent with a bow and the atlatl, a dart-throwing contraption from the Kiban jungle. Swords just felt oddly clumsy in her hands. But she knew precisely how to hold one and which stance to take, which was what she did. It was much heavier, of course, than most other swords she'd held. But she hefted it almost easily, which no normal woman could have done.

"It's a beautiful sword, Forgefire. Noxan blacksmiths are the best in the world, I hear. I have to agree." She'd commissioned her own daggers from Noxus. A man named Nolan, whom she knew had once worked for the royal castle. It had cost her a pretty penny, but for such fine work, she hadn't blinked an eye. "Ardanian work is primitive compared to this masterpiece." She sounded like she was exaggerating, but she spoke nothing but the truth. Ardany had an excellent standing army of finely trained warriors, but such a large army cost a lot to maintain, and their weapons were much more utilitarian. Lower quality steel, less push to keep them clean and sharp.

Aleksandra was indeed an excellent rider. But her horse was also exceptional, because Glass River horses were remarkably intelligent and easy to train once they took a liking to someone. Artemus didn't like her, but he loved her. And that was all that mattered. He could keep up a gallop for hours without complaint, and a mile-eating canter for days if need be. If she felt she was being followed, she could dismount and he would continue, putting more force into his hoof beats to make it seem as if he still carried her. She could teach him sound signals and he would remember them. He told her when danger was near and she never had to tie him to anything. She could simply drop his reins and he'd stay close.

Her horse was probably her closest friend. She didn't know if that was a good thing, really.

She knew much of Noxus, having lived here the most over the past twelve years. She loved the rolling green hills, the mild summers and gentle winters. She supposed it was in her blood to love the paradise kingdom. Her mother, a brothel whore, had been Noxan. Another reason her brothers had hated her so much. They would call her horrible things and pinch her arms. Filthy Noxan barbarian. Noxan whore-child. Why don't you fuck a goat, fur-cloaked gremlin? She shook her head and frowned. She would not let her memories ruin this paradise for her.

Aleksandra was delighted by Forgefire's choice of outing. She knew this place! She'd camped in this little glen twice or thrice before, bathing under a nearby waterfall each morning and catching an abundance of fat rabbits in her snares. There was a large patch of grasses and clover nearby which, sure enough, Artemus found immediately and began munching away. After she and Forgefire sparred, she'd show him the waterfall and the large flat rock that was always warm from the sun where they and their clothes could lay out to dry.

And then they began. She was still for a few moments, knowing she had the time to work out how best to disable Forgefire and gathering her strength. She would need it if she was to have any chance of beating him. And then, without any sort of warning, she struck. Lamely, that is. She went completely limp as if transformed into water, and then she struck a painful pressure point in Forgefire's arm to force him to let go. She slipped free, and their fight began in earnest.

It was one of the most challenging fights she'd ever been in. And the most fun. She wore a feral grin the whole time, laughing anytime one of them performed a particularly amazing or cunning move. Of course, the fun had to end eventually. A little less than ten minutes into their sparring, her injured foot got tangled in a long clump of grass and sent her barreling into him, shrieking with laughter as they crashed to the soft, springy ground. She knew she'd lost their fight as soon as she stumbled, so she let herself enjoy it as she landed half on top of him, a tangle of limbs and hair and clothes. She was still laughing, laying nestled against his side in the grass and feeling her heart race with adrenaline.

She tipped back her head, which rested on his outstretched arm, to look at his face. She was grinning, her face flushed and her hair plastered to the sides of her face with sweat. "I haven't had that much fun in ages!"