Lustbound JOI is a 3D animated relationship simulator built in Unity by FlashBangZ. It presents a fantasy setting where the player controls a male wizard who begins living with his witch girlfriend. The project is currently a demo prototype, so development remains ongoing, and its presentation uses 3DCG visuals with voiced characters.
Version v1.9.a9 was released on May 15, 2026 for Windows in English, without censorship. The latest update adds Companion Mode for all Patreons to test. This mode is intended to adapt to the player, with a partner that observes rhythm, learns preferences, and anticipates needs. Players can open customization through the disk icon at the top left. Many options, such as stage durations and arousal levels, can be changed during play with in-game handles and interface controls.
Developer's description
Demo Prototype
Lustbound is going to be an enchanting relationship simulator set in a fantasy world,
where you play as a sexy wizard moving in with his cute witch girlfriend
v1.9.a9
Companion Mode is finally avaliable for all Patreons to play and test!
What is Companion Mode?
Think of Companion Mode as adaptive gameplay that grows with you. It is designed to be a highly responsive, personalized experience where your partner actively observes your rhythm, learns what you like, and anticipates your needs.
Getting Started
If it’s your first time diving into Companion Mode, we recommend exploring the customization options first by clicking the
disk icon
in the top left. You have absolute control over your experience from start to finish.
On-the-Fly Adjustments:
Most settings—including stage durations, arousal levels, and poses—can be adjusted in real-time using the interactive in-game handles and UI.
Deep Customization:
For advanced fine-tuning or to manage your session presets, you can open the full
Companion Settings
menu at any time.
Developer Note:
Eventually, most (if not all) of these backend settings will be seamlessly integrated directly into the live gameplay.
Click to expand...
The Adaptive "Brain"
Companion Mode is powered by a system that actively learns your playstyle to deliver a seamless experience.
Smart Pacing:
The game tracks your time to climax. If your pacing consistently changes, the engine naturally adapts the session to match your rhythm.
Dynamic Speed:
When you manually adjust stroke speed during gameplay, the system takes notes. It gradually learns your preferred intensity for every single stage. Over time, each part of the encounter will automatically default to the exact speeds that fit your playstyle.
Session Stages
Every session flows through five distinct phases:
Warmup
,
Buildup
,
Main Course
,
Almost There
, and
Climax
.
Duration Control:
Your global "Time to Orgasm" setting dictates the base length of each stage.
Progress Tracking:
Meters at the bottom of the screen show your real-time progress toward the next phase.
Manual Overrides:
Use the in-game handles to tweak stage durations on the fly, or use the arousal slider to scrub forward and backward through a stage's progress.
Coming Soon:
Currently, your partner's arousal directly mirrors your own.
In future updates, she will develop her own independent internal experience.
Poses & Progression
You dictate the action. Using the in-game menu, you can whitelist specific poses for each stage or instantly trigger a pose change.
Seamless Transitions:
When it’s time to move to the next stage, she will ask if you are ready. You can choose to advance or simply say, "Not Yet." If you decide to linger, the system automatically recalibrates your session timing to account for the extra time spent in that stage.
Triggering the Finale:
Advancing to the final "Climaxing" stage is entirely in your hands. You must manually press the
"I’m Cumming!"
button or trigger it via voice command.
Voice Control
When Voice Control is enabled, you can communicate directly with your partner. She listens, interprets, and reacts to your spoken cues to adjust her speed and movement.
v1.8.13.1
( [ New Genital Option: Futa! ]
v1.8.12
We added another dildo variant for you to use and have fun with
[ Customization Improvements ]
The character customization system has been optimized to reduce slowdown during customization
to almost zero across most system hardware configurations - In
preparation for the new game mode
, we’ve added seamless equipping and removal of clothing items during gameplay. In addition, poses will automatically remove any clothing that is blocking entry for sex, and then put them back on when done.
[ New Customization Options ]
Added
one-piece crotchless lingerie/swimsuit
in three patterns.
[ New Poses ]
Added missionary legs spread
Added anal variant of Missionary
Added anal variants of Lean on Wall poses
[ Mod Support (WIP) ]
Stripped Odin dependencies from OhBits
and
all related assets in preparation for custom story and game mode modding.
This is really important, as this would've made it impossible to release a full modding option for people down the line.
[ Bug fixes ]
Crystal ball image search should now be working again
(We had to completely re-make the backend for this to work again
- Character models should no longer disappear when changing poses
- Breast physics should now properly follow different sized breasts
- Breasts should no longer poke through tops
- Character models should no longer turn into black silhouettes when removing clothing
- Cloth and hair physics should no longer slow down the game with error log spam when customizing characters
v1.8.11
[
Facial Animation System - First Pass ]
Completely overhauled Estelle’s facial animation
system with a broader range of expressions and improved ARKit face morphs.
Integrated
new facial expressions
during sex, including open/closed eyes, open/closed mouth moaning, subtle eyebrow movements, and aroused "bedroom eyes."
Facial animations are dynamically driven by SexFX
, our custom system that synchronizes audio, animations, and sex-based events to create a more immersive experience.
Major refinements to existing facial animations
for enhanced realism and emotional depth.
Added bridge to allow facial animation control via the OhBit story sequencer.
[ New Customization Options ]
Added
sliders
for eyebrow thickness, arch, and positioning.
Introduced
three new eyebrow
textures
Added a 2-in-1 dildo/vibrator hybrid.
Added Secretary style glasses.
Added Square style glasses.
[ New and Updated Poses ]
Added anal variant of Cowgirl leaning forward.
v1.8.10
New Animations / New Blowy rework / New Items & More!
v1.8.9
Hey there everyone! New version and more upcoming stuff yet again
v1.8.8
-Lovense Solace Pro should now be working as intended.
v1.7.7
N/A
v1.4.1
N/A
v1.3.2
N/A
v1.3.1
Fixed issues with Satisfyer Plug-ilicious 2 connections
Fixed issues with Satisfyer device identification
Added Lelo F1s v2 support
More support for Mannuo / Magic Motion / OhMiBod devices
May fix issues with windows Bluetooth on older Win 10 versions
Lovense Calor support
Folove series support
More WeVibe / Satisfyer support
[If you own any of these toys, we'd love if you can give us some feedback <3]
Fixes:
All existing sound clips have been cleaned up and have had their volume levels balanced.
Changed the spelling of Jack-Off Instructions, to Jerk-Off Instructions.
Fixed SexFX audio sources not getting reset between games when starting pose happened to be the same as previously active pose during the last session.
The volume settings panel now has a background that cover’s all the sliders.
Interacting with the free play panel or the debug panel no longer unintentionally moves the free camera.
Pressing the Escape key before the main menu has loaded will no longer bring the pause menu up.
Pressing pause and submitting or canceling a bug report during Free Play will no longer result in Estelle moving while the game is paused.
v1.0.3
- Fixed issues with Satisfyer Plug-ilicious 2 connections
- Fixed issues with Satisfyer device identification
- Added Lelo F1s v2 support
- More support for Mannuo / Magic Motion / OhMiBod devices
- May fix issues with windows Bluetooth on older Win 10 versions
- Lovense Calor support
- Folove series support
- More WeVibe / Satisfyer support
Player reviews
Player rating5.0 / 5 · 5 ratings
Written reviews5 · avg 4.6★
Positive (4–5★)80%
Latest review2026-08-14
What players say
Most players rate it highly for toy sync and animation, while one criticizes short content.
5★4
4★0
3★1
2★0
1★0
Players like
Good bluetooth toy sync and varied patterns
Polished visuals and appealing character models
AI adapts to user preferences
Common complaints
Limited content and short gameplay
Needs more customization options
Best for players who want toy-synced animation-first JOI content
Summarised from 5 written player reviews.
honk3212026-08-14★★★★★
Late 2026 1.9.something version Such an underrated gem with nearly infinite potential Only if it had more customization options and voice command options, maaan... If you have onahole that is probably the best game on this site or simulator rather…
Fomen2025-03-03★★★★★
Heh, that's an actually nice but very-very raw visual user interface for bluetooth toys. Sync is good; patterns are interesting and sort of accurate to what is happening on the screen. But the happening itself is kinda monotonous and obviously…
Bonerhat2023-11-14★★★★★
Really nice simple JOI instructor that's very visuals and animation first, feels very polished despite being a early demo. Screenshots in the OP look like shit because it's a debug mode of an old build, actual thing is much nicer…