Most people's first AI companion is a premade one — pick a face, say hello, see how the conversation feels. But you can also build a custom AI companion from scratch on Svila.io, and a companion you designed yourself tends to fit better than one someone else designed for a general audience.
This is the team behind Svila.io writing about how the custom companion creation flow works and why we made the choices we did. Building a companion from nothing is a different experience than picking one off a shelf — it asks you to decide, in plain language, who you want to talk to. That's a bigger design question than it sounds like, and it's the one this guide is about.
We'll walk through every part of creating a custom AI companion on Svila: the basics, the kind of companion you want, the description, personality mood, story worlds, portraits, and what happens after she exists. None of this requires technical skill — it's a short form, not code — but knowing what each field actually does will get you a better result on your first try.
On this page
- Why building your own AI companion matters
- How we think about companion customization
- The Basics
- 2. What Kind of Companion? — Choosing a Tone
- Description
- Personality Mood
- Story Worlds
- Portraits
- After Creation
- How we approached this
- How to get the most out of a custom AI companion
- Final thoughts
- FAQ
- A note from the team
01—Why building your own AI companion matters
Why building your own AI companion matters
A premade companion is designed to work reasonably well for a lot of people, which means it's rarely designed to work perfectly for any one person. Tone, humour, pacing, how much affection versus banter — these are preference-heavy, and preferences vary a lot from person to person. Custom creation exists to close that gap.
For Svila specifically, our crafted companions — Aria, Luna, Zara and Kai — each have a clear personality, but four characters can't cover every combination of personality, background and tone people want. Building your own is the honest answer to "can you make one that's more like X."
02—How we think about companion customization
How we think about companion customization
When we designed the creation flow, we tried to keep it to the choices that actually change how a companion feels day to day. That means:
- Who they are — name, gender, and the language they open in
- How they relate to you — the tone you choose
- What they're like — a description in your own words, covering personality, background and appearance
- The register they speak in — an optional personality mood
- Where the story is set — story worlds, for two Premium tones
- What they look like — portraits generated from your description
- What happens next — memory, and what you can and can't change later
Below is a walkthrough of each of those, in the order you'll meet them on the creation page.
The Basics
Name, Gender and Language
Creating a companion starts on the "Create Your Persona" page, which you reach from the + button in your companion list. The first fields are the simplest: a name (the only required field), a gender (female, male, non-binary, or not specified), and a language.
The language field sets the language she starts in, and it defaults to your browser's language. After that, she follows you: she replies in the language you write in, and if you ask her for a particular language she keeps to it for the rest of the conversation. She's at her most natural in widely spoken languages; in less common ones her writing can be noticeably less fluent.
- What it does
- Sets the companion's name, gender and opening language.
- Best for
- Everyone — it's the part of the form you can't skip.
- How it works
- Name and gender go into the instructions the companion follows in every conversation; the language sets her opening default.
- Why we built it
- A name and a gender are the minimum a character needs before anything else makes sense.
- Bottom line
- Fill these in quickly — the choices that shape her most come next. [Try Svila free](https://svila.io)
04—2. What Kind of Companion? — Choosing a Tone
2. What Kind of Companion? — Choosing a Tone
This is where you decide how the companion relates to you, and it's the single most important choice on the page. The form offers four cards: "A supportive friend to talk to", "A caring romantic partner", "A flirty, magnetic companion" and "Someone who says the quiet part". The first two are free; the last two are Premium.
Behind those cards are Svila's tones. Open "Advanced customization" and you'll see all eight: Friendly, Romantic and Sweet on the free plan, plus Flirty, Dominant, Teasing, Uninhibited and Fantasy on Premium. A Friendly companion stays platonic. Romantic and Sweet are warm and affectionate. The Premium tones each have a sharper character — Dominant decides things and says so, Teasing needles you for sport, Uninhibited says the blunt thing out loud, Fantasy speaks from inside another world.
The tone also sets how far her mood can move during a conversation. Moods shift automatically based on her own replies — neutral, playful, flirty — and the tone caps them: a Friendly companion stays neutral, Romantic and Sweet can reach playful, and the Premium tones can reach flirty. You don't pick the mood in the chat, and it doesn't change with how long you've been talking.
What it does: Sets the baseline relationship and style of every message from the first one onward. Best for: Avoiding an early mismatch between what you want and how the companion talks. How it works: The tone is saved with the companion when you create her and shapes every reply she writes. Why we built it: Getting the relationship right up front beats trying to re-explain it in the first few messages. Bottom line: Decide this deliberately — the tone is fixed once she's created.
Description
Personality, Background and Appearance
The description is optional, but it's the field that does the most work. Whatever you write here is used as her character in every one-on-one conversation, and the appearance details in it shape her portraits. The page puts it plainly: appearance details (hair, eyes, body type, accessories) shape the avatar; personality details shape how they chat.
A sentence like "dry sense of humour, doesn't take herself too seriously, asks a lot of questions" does real work. So does a line of background — where she grew up, what she does for a living, what she cares about — which gives her consistent material to draw on when you ask her something personal. There are no separate backstory or trait fields: this box is where all of that goes. If you leave it empty, she gets a short default personality based on her tone.
Companions must be adults. The form rejects descriptions that describe a character as under 18.
- What it does
- Gives the companion a specific personality, history and look in your own words.
- Best for
- Anyone who wants a particular character rather than a general type.
- How it works
- Your description becomes her character in one-on-one chats and informs how her portraits are drawn.
- Why we built it
- A couple of well-chosen sentences produce a more distinctive companion than a long list of checkboxes.
- Bottom line
- This is the step that turns "a tone" into "a character" — write it before you press Create, because it can't be changed afterwards.
Personality Mood
The Register She Speaks In
Also under "Advanced customization" is a Mood field with six options: Mysterious, Cheerful, Dark, Playful, Melancholic and Sensual. This isn't the same as the neutral / playful / flirty mood that moves during a conversation. It's a fixed register that colours how she talks — cryptic and slow to reveal herself, bright and easy, drawn to the shadowed side of things, wistful.
Not every mood works with every tone. With a Friendly tone the field is disabled, because Friendly companions don't use one. With Romantic or Sweet, the more intense options are softened to Playful. The form greys out options that won't take effect, so what you can select is what you'll get.
- What it does
- Adds a consistent emotional register on top of the tone.
- Best for
- Fine-tuning a companion whose tone is right but whose voice needs a particular colour.
- How it works
- The mood is saved with the companion and included in her instructions, within the limits of her tone.
- Why we built it
- Two companions with the same tone can still feel very different, and mood is the quickest way to get there.
- Bottom line
- Optional, but worth a look — the default is Playful.
Story Worlds
Where the Story Takes Place
If you're on Premium and choose the Uninhibited or Fantasy tone, the form shows story worlds: ready-made settings that give her something to be part of. Uninhibited offers Workplace, Small town and On the road settings; Fantasy offers Otherworldly, Historical, and Arts & sciences settings. Examples include Late Shift, The Only Café, Night Train, Vampire Court, Regency Season and Observatory Nights.
You can pick one setting per category, and an otherworldly setting can't be combined with a grounded one.
- What it does
- Places the companion in a specific setting she brings into your conversations.
- Best for
- People who want a story with a premise, not just a conversation.
- How it works
- The settings you pick are saved with the companion and added to her instructions.
- Why we built it
- A companion with a world to talk from has more to say than one talking from nowhere.
- Bottom line
- A Premium extra for two tones — skip it if you just want to talk.
Portraits
Putting a Face to the Companion
You don't design the portrait separately. When you press "Create Persona", Svila starts drawing her automatically and takes you straight to the chat while it works. It first creates one reference face from your description, then one image for each mood her tone can reach: one portrait for a Friendly companion, two for Romantic or Sweet, three for the Premium tones.
There are no style presets to choose from and no regenerate button, so the appearance details in your description are your only lever — be specific about hair, eyes, build and style if you care about the result. Each mood image is drawn from the same reference face, but the images can drift and won't always look like exactly the same person.
Svila.io is for people aged 18 and over, and mature themes are welcome — attraction, conflict, jealousy, heartbreak, the slow burn of a real relationship. It does not generate sexual content, in conversation or in the portraits it draws.
- What it does
- Generates a reference face and a portrait for each mood her tone can reach.
- Best for
- Giving a written character a face you'll see throughout the conversation.
- How it works
- The portraits are drawn from the appearance details in your description as soon as she's created.
- Why we built it
- Drawing the face after the character is defined produces a portrait that matches who she is.
- Bottom line
- Put the appearance details in the description before you press Create — that's when the portrait is decided.
After Creation
Memory, and What You Can't Change
Once she exists, the companion starts learning about you. Every few messages, she picks out facts from your conversation and keeps them in your Memory Journal, and relevant facts are brought into her replies later. At /journal you can read what she's kept, edit a fact, pin the ones that matter, and forget ones you don't want her to keep. Facts about you in general — who you are, what you like, your boundaries — are shared by all your companions; details of your relationship with one companion stay with her. Facts about sexual content aren't stored.
What you can't do is edit the companion herself. Her name, description, tone, mood, language and story worlds are fixed once you press Create. If you want a different version, create a new companion with the changes and delete the old one — but note that deleting a companion permanently deletes her Memory Journal and any group chats she's part of.
- What it does
- Builds up memory as you talk; the companion's own settings stay as you created them.
- Best for
- Knowing what to get right on the form, and what will take care of itself afterwards.
- How it works
- Memory is added from conversation and managed at /journal; the companion can be deleted but not edited.
- Why it works this way
- A companion's memories belong to the character you actually talked to.
- Bottom line
- Take an extra minute on the form — there's no edit button afterwards.
10—How we approached this
How we approached this
This guide describes the creation flow as it works today, field by field, and the reasoning behind each step. We haven't included figures on how people use the form, because we'd rather not present impressions as data.
We also left out a detailed technical explanation of the underlying model and image pipeline, since this guide is meant for someone creating a companion, not evaluating our architecture.
11—How to get the most out of a custom AI companion
How to get the most out of a custom AI companion
- If you're brand new: Start with a name, a tone card and two or three sentences of description. Send a few messages and see how she feels.
- If your first attempt feels flat: Create a new version with a more specific description — a line of background usually fixes generic-feeling replies — and delete the one that didn't work.
- If you want a specific look: Put hair, eyes, build and style in the description before you press Create; that's what the portraits are drawn from.
- If you're setting up something long-term: Take the tone choice seriously up front, because it can't be changed later.
- If you want her to know you: Just talk. She adds facts to her Memory Journal as you go, and you can pin the important ones at /journal.
12—Final thoughts
Final thoughts
Creating a custom AI companion is less about filling out a form correctly and more about deciding, in specific terms, who you want to talk to. The fields exist to help translate that decision into something the model can consistently act on — but the decision itself is the part that matters.
Because a companion can't be edited once she's created, it's worth a few minutes on the description and tone. If the first one doesn't land, making a second one takes no longer than the first.
FAQ
Do I need any writing skill to create a custom AI companion on Svila?
No. Short, plain sentences work better than elaborate character write-ups. The description is optional, and a couple of clear sentences is plenty.
Can I change my companion's personality after I've already been talking for weeks?
No. A companion's name, description, tone, mood and settings are fixed once she's created. You can create a new companion with the changes, but deleting the old one permanently deletes her Memory Journal and any group chats she's in.
Is custom creation available on the free plan?
Yes. The free plan lets you create your own companions with the Friendly, Romantic or Sweet tone, alongside chatting with Aria, with 20 messages a day. Premium adds unlimited messages (within fair use), the other five tones, story worlds, Luna, Zara and Kai, and group chat with two companions at once.
Can I give her some memories before we start talking?
Not on the creation form. Anything you want her to know from the start can go in the description; after that, she adds facts to her Memory Journal from your conversations, and you can edit, pin or forget them at /journal.
Do I have to fill out every field?
No. Only the name is required. Gender, description, mood and story worlds are optional, and tone and language have defaults — but none of them can be changed after you create her.
Can I choose her voice?
No. There's no voice setting when you create a companion; she talks with you in text.
14—A note from the team
A note from the team
This post is written by the team behind Svila.io. The features and choices we describe are ones we designed and shipped — so our perspective is first-party, not neutral. We try to be honest about the trade-offs, but you should always try things yourself and form your own view.
Last updated September 2026.
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