Fanfic Prompts: 50 spicy fanfic ideas to start tonight

Short answer: the best fanfic prompts give you a pairing, a setting, a dynamic and a hook in one or two sentences. Below are 50 spicy fanfic ideas grouped by trope, from enemies to lovers to coffee shop AUs. Every one works with any fandom, as long as both characters are adults in canon.

Swap in your own ship, paste the prompt into an AI fanfic generator, and you can have chapter one in under a minute.

A quick ground rule before you start: every prompt here assumes adult characters and enthusiastic consent. If your favorite characters are teenagers in canon, pick a different pairing. “Aging them up” does not count.

Updated November 2026.

How to use these fanfic prompts

Each prompt is written with placeholders, so it fits whatever fandom you love. “A” and “B” are your two leads. Replace them with your characters, add one detail from canon (a scar, a rivalry, a running joke), and the prompt becomes yours.

Pick the trope first, since it sets the pace, then choose the heat (slow burn or explicit) before chapter one. Keep your version to three sentences or fewer so the characters still have room to surprise you.

Fanfic tropes cheat sheet

Not sure which trope fits your ship? This table matches the most popular fanfic tropes to the kind of story they create.

Trope	Best for	Pace	Works well with
Enemies to lovers	Rivals, opposite sides, sharp banter	Slow burn	Canon rivals, villains with a code
Fake dating	Pining, jealousy, accidental honesty	Medium	Friends, coworkers, exes
Forced proximity	Tension with nowhere to go	Fast	Any ship that avoids each other
Only one bed	Comedy that turns tender	Fast	Road trips, missions, inns
Alternate universe (AU)	Fresh settings for familiar people	Any	Ships that never got time in canon
Hurt and comfort	Emotional intimacy, aftercare	Medium	Warriors, medics, stoic characters
Second chance	Exes, history, regret	Slow burn	Characters separated by canon events
Secret relationship	Sneaking around, close calls	Medium	Rival factions, workplace ships
Power dynamics	Consensual dominance, negotiation	Any	Leaders, mentors who are peers now
Holiday and seasonal	Cozy, festive, low stakes	Fast	Found family, soft ships

Enemies to lovers prompts

The most requested of all fanfic tropes, for good reason. The fun is in the friction: two people who know exactly how to get under each other’s skin, discovering that the skill works both ways.

A and B are rival commanders forced into a ceasefire negotiation in a neutral city. The talks drag on for a week, and every night they end up in the same hotel bar, arguing until closing time.
B has spent years trying to arrest A. Now A is the only person who can clear B’s name, and the price is B’s help with one last job.
Two rival chefs are booked to cater the same wedding after a scheduling disaster. They share a kitchen for three days, and the bride wants one menu.
A wins the election B was sure of. B becomes A’s deputy, with full access to A’s calendar, office and very bad habits.
After a battle, A and B are the only survivors on opposite sides. They need each other to get home, and neither will admit the other is good company.

Start an enemies to lovers fic in the fanfic generator, or read our guide on how to write fanfiction with AI for a slow-burn workflow.

Fake dating prompts

Fake dating works because the lie gives both characters permission to act out what they actually want. The best versions make the fake part slip early and often.

A needs a date to a former partner’s wedding. B owes A a favor and agrees, then turns out to be far too good at pretending.
To get a lease in a couples-only building, A and B sign as partners. The landlord lives next door and is very observant.
A and B pose as a married couple to infiltrate a luxury retreat for a mission. The cabin has a hot tub, thin walls and a schedule of couples activities.
B’s family keeps setting B up on dates. A offers to play the serious partner for the holidays and overcommits to the role by day two.
A public figure needs a steady partner for a press tour. B is the bodyguard who takes the job, under strict rules that both of them break.

Start a fake dating fic in the fanfic generator.

Forced proximity prompts

Lock two people in a small space and every glance gets louder. Forced proximity prompts are perfect for a fast first chapter.

A snowstorm traps A and B in a mountain cabin after a mission goes wrong. The radio is out, the firewood is low, and they have not spoken civilly in a year.
An elevator breaks down between floors late at night. A is the coworker B has been avoiding since an awkward office party.
A and B share a tiny cabin on a long sea voyage. There is one porthole, one lamp and nowhere to storm off to.
A quarantine order keeps A in B’s apartment for two weeks. B has strong opinions about how the dishes are done.
A spaceship’s life support fails in every room but one. A and B have twelve hours before rescue and very different ideas about how to pass the time.

Start a forced proximity fic in the fanfic generator.

Only one bed prompts

The comedy of the setup gives way to the honesty of 3 a.m., when neither character can pretend to be asleep.

A and B arrive at an inn after a long ride and find one room left, with one bed. A offers to take the floor. B tells A not to be ridiculous.
A booking error at a conference hotel leaves two rival academics in one suite. The sofa is shorter than either of them.
On a road trip, A and B pull into the only motel for fifty miles. There is one bed, a broken heater and a long night ahead.
A safe house was stocked for one agent. Now there are two, and only one bed that is not covered in maps.
A and B have shared a bed on missions for years, purely for practical reasons. Tonight, one of them finally says something about it.

Start an only one bed fic in the fanfic generator.

Alternate universe (AU) prompts

AU prompts drop familiar characters into a new world, which is a great way to explore a ship canon never had time for. Keep their personalities; change everything else.

Coffee shop AU: A runs a small cafe and B is the regular who orders the same thing every day and leaves a better tip each time. Today B finally stays until closing.
Modern AU: A and B are neighbors in an apartment building with paper-thin walls, and they have been leaving each other passive-aggressive notes for months.
Royalty AU: A is a foreign monarch and B is the ambassador assigned to keep A out of trouble during a long state visit.
Rock band AU: A is the lead singer and B is the new guitarist, hired on the eve of a tour with a lot of shared hotel rooms.
Fantasy AU: A is a mercenary hired to escort B, a mage with a price on their head, across a kingdom where everyone wants that bounty.

Start an AU fic in the fanfic generator. AUs are also where a Lorebook earns its keep: store the new world’s rules once and every chapter follows them.

Hurt and comfort prompts

Hurt and comfort prompts give stoic characters a reason to let someone in. The spice comes later, after the trust.

A comes back from a mission injured and refuses help. B, who has medical training and no patience, patches A up anyway.
B has a nightmare in the middle of a long campaign. A, on watch, sits with B until morning and finally hears the whole story.
After a public defeat, A disappears. B tracks A down to a rented room and refuses to leave until A eats something.
A and B survive a disaster and spend the first quiet night afterward taking care of each other, slowly and carefully.
A burns out after years of holding everything together. B takes A away for a week, with no plans except rest, and the rest turns into something else.

Start a hurt and comfort fic in the fanfic generator.

Second chance and exes prompts

Second chance prompts come with history built in. The characters already know each other’s weak spots, which makes every scene charged.

A and B broke up years ago when canon pulled them apart. Now they are seated next to each other at a mutual friend’s wedding, and the open bar is very open.
B returns to the city A never left. They agree to one drink to clear the air. It is not one drink.
A and B were engaged before the war. Now they meet again as officers on opposite sides of the peace talks.
A finds the letters B never sent. A decides to answer them in person.
Years after splitting up, A and B are hired to work together on one last job. The job takes a month, and they share a tent.

Start a second chance fic in the fanfic generator.

Secret relationship prompts

Secrets add stakes to every touch. These prompts are great for multi-chapter fic where the question is not if they get caught, but when.

A and B lead rival factions and meet in secret every full moon. This month, someone has followed one of them.
Two coworkers are in a secret relationship at a company with a strict policy. Then they are both nominated for the same promotion.
A is a famous duelist and B is A’s most persistent opponent. Publicly they are enemies. Privately they have been together for a year.
A and B have to hide their relationship during a week-long family gathering at a crowded country house.
B is A’s bodyguard, and the relationship is against every rule in the contract. A new threat means B has to stay closer than ever.

Start a secret relationship fic in the fanfic generator.

Power dynamics prompts

Power-dynamic fic is about trust as much as heat. Keep it consensual and negotiated: the characters talk about what they want, and either one can stop.

A is used to giving orders on the battlefield. Off duty, A asks B to take control for one night, and they agree on the rules first.
B is a strict instructor at a fencing club and A is the adult student who keeps losing on purpose. After class, they talk about why.
A and B have played a long game of rivalry for years. They finally sit down and negotiate a very different kind of contest.
A, a ruler who controls everything, wants one place where someone else decides. B, a trusted adviser, is willing, with a safeword.
A and B make a bet. The loser follows the winner’s instructions for a weekend, within limits they set together and write down.

Start a power dynamics fic in the fanfic generator, and check the content guidelines before you begin: consensual adult fiction only.

Holiday and seasonal prompts

Seasonal fanfic ideas are cozy by design, which makes them perfect for fluff that turns spicy late at night.

A hosts a holiday party and B is the last guest to leave, staying to help clean up and finding excuses not to go.
A and B are snowed in on New Year’s Eve and decide to make the countdown count.
A summer festival, a lantern release and a kiss neither of them planned, between two characters who have been dancing around it for years.
B agrees to help A decorate for the season. A is very particular about the lights, and B is very good at distraction.
A and B take a winter trip to a hot spring inn, one private bath and a long, quiet evening.

Start a holiday fic in the fanfic generator, or browse fanfic in the RedQuill library for seasonal stories other writers have shared.

How to turn a fanfic prompt into a full story

Here is how to turn one of these fanfic ideas into a multi-chapter fic on RedQuill.

Paste the prompt. Replace A and B with your characters and add one canon detail. One or two sentences is plenty.
Add character profiles. Write each lead’s personality, speech habits and history. The AI uses the profiles every chapter, which keeps them in character.
Set the spicy level. Choose slow burn or explicit before chapter one, so the story builds toward the right payoff.
Pick a chapter length. Standard is about 1,000 words. Long and Epic give big scenes more room.
Continue chapter by chapter. Steer each chapter with a short note (“they argue, then she leaves”) and edit any line you want to change.
Use the Lorebook for longfic. Store canon facts, places and AU rules, so chapter twenty still remembers chapter one.

For a real example of this workflow, read how one writer uses RedQuill for fanfiction. If you are still choosing a tool, our roundup of AI fanfic generators compared ranks eight options.

How to write your own fanfic prompts

Once you have used a few of these, you will want to write your own. A good prompt has four parts:

Who: the pairing, and one trait each that drives the conflict (“A never asks for help; B never stops offering”).
Where: a specific setting, ideally one that forces them together.
The dynamic: the trope, in plain words: rivals, fake dating, second chance.
The hook: the thing that makes tonight different from every other night.

Do you need a fanfic prompt generator?

A fanfic prompt generator spits out random combinations of trope, setting and twist. Fun when you are stuck, but random prompts often miss what makes your ship tick. A better approach is to treat a list like this one as a menu, then let an AI story tool write the first chapter from the prompt you pick.

That is the difference between a prompt generator and a fanfic generator: one gives you an idea, the other gives you the story. RedQuill does the second, and it is free to start with free daily quills and no card. If you want to compare free options first, see our guide to the free AI fanfic generator choices.

A note on fandom etiquette

Fanfic is non-commercial fan work, and the community has its own norms. If you post a fic you wrote with AI help, label it, and follow each archive’s rules on AI-generated works. AO3 allows AI-assisted works with tagging at the time of writing, but check its current policy before posting. Our list of sites like AO3 covers other places to share adult fic.

Fanfic prompts FAQ

Where can I find good fanfic prompts?

Lists like this one are a good start, and fandom communities often run prompt challenges. The best fanfic prompts are specific: a pairing, a setting, a dynamic and a hook in one or two sentences.

What are the most popular fanfic tropes?

Enemies to lovers, fake dating, forced proximity, only one bed, hurt and comfort, and alternate universes (especially coffee shop and modern AUs) are among the most popular fanfic tropes. Slow burn pairs with almost all of them.

Is there a fanfic prompt generator?

Yes, several sites generate random fanfic prompts. If you want the story and not just the idea, paste a prompt into an AI fanfic generator like RedQuill, which writes a full first chapter in under a minute and lets you continue chapter by chapter.

Can I use these fanfic ideas with any fandom?

Yes. Every prompt uses placeholders, so it works with any fandom where both characters are adults in canon. Add one canon detail to make it feel like your ship.

Can AI write spicy fanfic from a prompt?

Adult story platforms like RedQuill can, for consensual fiction between adult characters, with a spicy level you control. Mainstream chatbots restrict explicit content at the time of writing.

How long should a fanfic prompt be?

One to three sentences. Enough to name the pairing, the setting and the hook, short enough that the story still has room to surprise you.

Start your fic tonight

Pick a prompt, swap in your ship, and let an AI fanfic generator write chapter one while you decide where it goes next. It is free to start, with free daily quills and no card. Generate your fantasy.