How to Create an AI Girlfriend: Persona, Memory and Media

If you want to create an AI girlfriend yourself, you no longer need to be able to program. Many companion apps let you set up your own character. In an ordinary AI you can go further with a good instruction. And if you are technical, you can build something yourself with a language model, a memory, a voice and an image generator.

Whichever way you do it, one rule always applies: start with the character. Most people do it the other way round. That is why so many home-made AI girlfriends sound alike as soon as they say something.

Step 1: how should a conversation with her feel?

"A nice girlfriend" is too vague. A language model can't do anything with it. Describe instead what it feels like to talk to her. For example:

• direct, but not rude;
• dry humour;
• likes cycling and bad films;
• often disagrees with you.

That gives a language model far more to hold on to.

Step 2: make it concrete

"Funny", "sweet" or "mysterious" means something different to everyone. So describe what she does.

Not:

She is funny.

But:

She has a dry sense of humour, teases you now and then and never explains her jokes.

Not:

She is confident.

But:

She says what she thinks and doesn't back down straight away when you disagree.

The more concretely you describe her behaviour, the better she stays herself.

Step 3: the way she talks

How she talks matters more than her backstory. Does she send short messages or long walls of text? Does she use emoji? Is she careful or blunt?

If you want a Dutch AI girlfriend, write down literally that she speaks ordinary Dutch the way people text, not like a translated assistant. Without that sentence many models fall back on correct but stiff. More on that in AI girlfriend in Dutch.

Step 4: a background, but not too much

A few fixed facts help keep her consistent: her rough age, what work she does, where she lives, what she likes doing, a few things she has been through.

You don't need a twenty-page biography. The more you fix in advance, the less room there is for a conversation that goes somewhere. So leave things open. That she used to play hockey, she can tell you herself.

Step 5: give her her own taste

This is the easiest way to make her less standard. Give her a music style she is a fan of, a film genre she can't stand and a country she still wants to visit.

And not everything has to match your taste. An AI girlfriend who likes exactly the same things as you feels like a mirror after a week.

Step 6: think about her memory

If the app can remember things, decide what is worth keeping:

• your name and how you want to be addressed;
• people who come up often;
• things that are about to happen.

Not everything needs to go in. A good memory chooses, and you have to be able to correct it. How that works is in AI girlfriend with memory.

Step 7: contradict her

As long as you have predictable conversations, every character seems stable. The real work starts when you push back:

But yesterday you said you hated that.

Or:

I actually think that film is brilliant.

Does she react logically, with what she said earlier in mind? She can change her mind, people do too. But for a reason, and not because you happen to see it differently.

Step 8: only now, her looks

Only now her appearance. Besides her face and hair, describe the style around it: clothing, the kind of photos, the setting, the light, make-up, the overall feel.

If you want several photos, choose recognisable over spectacular. A slightly simpler look that shows the same woman in every photo works better than one beautiful picture you can never match again.

Step 9: a voice that fits

A voice can make a character stronger, or ruin it in one sentence. Sounding nice matters least. Ask yourself:

• Does it sound like normal Dutch, or like a foreign voice reading Dutch aloud?
• Does her humour come across when spoken?
• Does everything sound like an advert?

The more often you hear her, the more that voice becomes part of her. So choose carefully.

Step 10: make a fixed test list

Software makers test with fixed scenarios. Do the same. Write down twenty or so messages, for example:

• an ordinary greeting;
• bad news;
• a disagreement;
• a reference to yesterday;
• just "hm".

When you change something about her character, send that list again. That shows you whether she gets better on one point and suddenly odd on another.

Building it yourself with a language model

Technical? Then you can put a companion together yourself. Roughly, it looks like this:

app → character and context → language model → memory → reply

Then come parts for speech to text and back, image generation, filtering unwanted content, user profiles and storage.

The connections themselves aren't the hard part. The hard part is making all those separate systems present one and the same person.

She is never finished

You don't make a good AI character in one go. Only when you really talk to her do you notice she asks too many questions, gives answers that are too long or says yes to everything. Then you adjust the description, and carry on talking.

Keep it simple

You don't need a hundred settings. Start with a clear character, a way of talking and a handful of her own preferences. Once that is in place, make it more complicated.

Want to understand first what makes a companion different from an ordinary chatbot? Read AI girlfriend vs chatbot.