NSFW AI Character Bible: One Page That Keeps a Character the Same

Open a blank note and write a name for someone who does not exist. Ours is Inés Calloway, an invented adult, and by the end of this post she will have a one-page bible: one description line you paste into every prompt, a short list of what never goes into it, and a card to keep it all on. Inés is an example, not a template to copy. Take the order, not the woman.

Start with an age, said as an adult

The first words on the sheet say who she is in years: “a woman in her mid-thirties”. A band reads more naturally than an exact number, and it does two jobs. It pushes the model toward adult features instead of a vague, smooth average, and it puts the first rule of this work at the top of the page where you cannot forget it: every character here is an adult and fictional. Everything below is written for characters like that, and the rules at the end explain what happens to a prompt that says otherwise.

The line, slot by slot

The line is one sentence, written in the same order every time, so two versions can be compared at a glance. Seven slots, with Inés filling each:

• Age and noun: a woman in her mid-thirties
• Build: tall and athletic, broad shoulders
• Hair: shoulder-length wavy chestnut hair with a side parting
• Skin: warm olive skin, light freckles across the nose
• Eyes: hazel eyes
• One signature detail: a thin crescent scar through the left eyebrow
• Wardrobe anchors: a charcoal wool coat and a thin silver chain

Assembled, the line reads:

Inés, a tall athletic woman in her mid-thirties with broad shoulders, shoulder-length wavy chestnut hair with a side parting, warm olive skin with light freckles across the nose, hazel eyes, a thin crescent scar through the left eyebrow, wearing a charcoal wool coat and a thin silver chain.

Why only one signature detail? Every other slot can be filled by a plausible average. A scar, a gap in the front teeth or one grey streak is what makes a viewer say “that is her”. Choose one: several small details compete, and in our experience the quiet ones are dropped first. The hair slot wants length against the body and a texture, not an adjective; the words that render are collected in hair and makeup for character portraits, and the bible only has to fix them once. Wardrobe anchors are the two pieces she is known for, not a whole closet. For fabric words that hold their shape, see outfits and fabrics.

What stays out of the line

A bible is as much a list of exclusions as of facts. The line holds what is true of Inés in every picture, and nothing else:

• Anything that changes shot to shot. Pose, expression, light, setting, camera and time of day belong in the scene part of the prompt, after the line.
• Praise.“Beautiful”, “perfect” and “stunning” describe your opinion, not her, and every model already leans that way.
• A real person’s name or “looks like” anyone. It breaks the rules below, and it pulls the face toward someone who has not agreed to it.
• Style and quality tags. Photographic, painted or anime is a decision about the picture, not the person. Keep it on its own line so you can change it without touching her.
• Negatives.“No tattoos” puts a tattoo in the sentence. Say what she has, not what she lacks.
• Any word that hints at youth. Never, in any form. See the rules below.

Keep the line short enough to read in one breath. Long descriptions do not make a face more consistent, they make the prompt harder to render, which is the argument made at length in why a description alone cannot hold a character.

The line and the reference image

The line is the recipe; a reference image is the face. So the bible has two forms. The full line is for casting: the first drafts, before you have a render you want to keep, and any family that takes no reference at all. The short line is for when a reference is attached, and it keeps only what a picture cannot show you: the wardrobe anchors and the signature detail, for the angles where the scar is turned away. Face, hair and skin come out of the short line, because naming an attribute you are already preserving turns it into something the model draws afresh.

Once one render is Inés, keep that file and attach it. The first reference is the one the framing follows, and a request with a reference goes through the edit model, which is why the cheapest image family, which takes none, is a casting tool and not a series tool. How many references a picture accepts, and what each one adds to the cost, is on the product page. The mechanics, including using your own photo, are in editing with a reference image. For a character you generate, the reference is a render of your invented character, never a photo of someone real.

When she drifts

She will. The hair creeps past the shoulder, the scar vanishes in a three-quarter turn, the coat turns navy. Do not answer drift with more adjectives; the line gets longer and vaguer and the next render drifts somewhere else. Work it like a lab note instead:

1. Save the drifted render beside your keeper and find the one slot that differs.
2. Ask whether the line was vague there or the scene overpowered it. Hair that wanders usually wants a length against the body (“to the collarbone” instead of “medium”). Eyes that change under a coloured light are the scene’s doing, not the line’s.
3. Change exactly one thing in the line and run a few cheap drafts. A detail that keeps vanishing can move earlier in the line and say which side it is on.
4. If it helped, call it version two, and write one sentence on why. If it did not, go back to version one.

The same discipline is what keeps a set together when the picture changes around her; the fixed half of a story series across six frames is exactly this line.

Where the card lives

One card per character, in a plain text file or whatever notes you already open every day. Inés’s holds: her name and the version number, the full line, the short line, the exclusion list, the file name of her keeper reference, and one line saying what changed in the last version and why. Nothing else. How to keep a prompt collection that stays usable is the subject of keeping a prompt library; the bible is one entry in it, the one you open most. Paste from the card. Retyping a line from memory is how version one quietly becomes version one-and-a-half.

The lines that are not up to you

Every character is an adult and fictional, and the product enforces the first half of that in code. Before a coin is spent, and before a prompt is sent to our image provider, the text is checked: a stated age under 18, in digits and in several languages, words that mark a character as a minor, a school setting paired with youth words, and family-coded roleplay with sexual context are refused outright. The check logs which rule fired, not your prompt, and it is a pattern check, not a judge of intent, so a plainly written line like Inés’s is the safe way to use it. A stated adult age never rescues a child word.

A real person’s likeness is not yours to use without permission, and our terms forbid sexual or intimate imagery of a real, identifiable person. A bible describes someone invented. And minors, age-play and non-consent are never a subject we write about except to refuse them, whatever the wording and whatever backstory comes with the prompt. What is legal where you live is a separate question, answered in what is and is not legal.

What a bible cannot do

It cannot guarantee the same face. A good line reduces drift, a reference reduces it further, and every generation is still a fresh draw: expect a resemblance you recognise, not a copy. It cannot repaint one detail, either: an edit with a reference redraws the whole picture, so a fix to the coat can move the hair. A line tuned on one model family may need a retune on another. Failed generations are refunded; a finished render that simply is not her is not, which is why you test the line on cheap drafts, as in draft first, spend later, before you spend on the keeper. The costs are on the product page. When you are ready to try the card, open the image studio and paste the line. You have finished the bible when someone else could read the card and draw the same woman.